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air intake (heated vs non-heated) and IAC bypass
#1
now here is a debate.

various internet 'sources' claim that heated air intake leads to better fuel efficiency by lowering the induction resistance. from what i can tell, since the IAC and ISC get heated (via hot engine coolant directly), the temperature of the air induction gets elevated.
so:

1.what happens (to fuel consumption) if i completely bypass the 'heating circuit' of ISC/IAC? (and thus cause 'colder' air intake temps?)

2.what happens if i block the IAC competely? mine suffered from too high cold rpm (2k and more; classic symptom of high-mileage vitaras), so i had it partially blocked (with RTV) till i got ~1500 cold rpm (which is fine for me). i also attached a 2k ohm resistor in parallel to the ECT to (partially) counter-act the AFR ratio when cold (otherwise it runned rich as a pig untill IAC closed). only bad symptoms i get is engine shacking for a couple of seconds in cold weather mornings.
Vitara 1998, 1.6L/16v, 5door, 5speed, G16BS.
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#2
there is no debate, all this is law now, the EPA here regulates this, end to end. (when the cat is dead, as it is cold, smog happens and they do care and do regulate this greatly ! (grams of HC, started!cold or hot) and more each year , heck in EU they now regulate CO2. (means tiny engines)_! not just HC,

no car stated, errrrrrrr ok you have posts here, 1998 G16b non usa car, no country stated yet.
but im too lazy to read all your 14 post to discover car, , do a signature, in you account, so we dont have search deep to find out what you drive.
in the usa this is law.(and in EU)

the engine does not know if car is in Alaska or in KeyWest.not really. (beyond 2 sensors.IAT/ECT)
so it heats the the whole intake, system and head the isc but the isc is electric and is not effected by heat,. but the ISC on the 8v heats the TB on the 16v it heats up the plenum box. (nothing trival here at all this is by design and laws of nations)
the iAC valve is a thermal air valve if not heated it goes dead and leaks air and engine screams a 3000 rpm at idle, that be bad.
the ECU is tuned to burn the fuel based on water temp and air temp (IAC) to the fuel vapor pressure specs. (a fuel spec that is also regulate by law.)



the fuel will not vaporize cold if that happens, the engine makes smog, huge smog (HC), so every effort is made to heat those parts fast.
IF the didnt, they be like VW is now. today. DOA, no imports to USA , (still playing out) not to mention the MPG lies told by VW, (huge whoppers)

the heated air allows the fuel to vaporize, easy,
the engine does not burn liquid fuel, if it is liquid it will pool up in the intake plenum like all 8v love to do and are now illegal here for this 1 fact.
Calif banned it first.

with G16b are port injection running dry runners., direct injection systems are even better for this reasons.
The injector needs to vaporize the fuel not stay drops of fuel, see? drops bad, vapor best.

on cold start the IAC is open below 150F, (colder more its by Design) that makes the engine race cold, and is by law here, to burn the fuel best, cold.
the cat is dead, cold, as is the 02, so HC can be nasty with 1billion cars puking HC on earth, huge....

so it makes smog cold, unless engine is races. it's hard coded into the ecu and the IAC sets all idles speeds below 150f,.
Rule 1 of all ECU , never lie to the ECU, it will calculate wrong, every time,.... the ecu runs tables , for many things, so of you lie to it ,it uses the wrong tables.
you cant change that, unless , taking the IAC apart seems fun. once apart what would you do next attack the wax pellet and shim it?
nah...
or as you say block it with a solid gasket.
then the engine floods starting it. The block here is a huge lie to the ECU, the ecu then over injects for this lie. (making your too rich more rich) a fact.
Id bet yours system has problems. but I really dont know why you know its rich at cold idle, at all.
after all the ECU knows IAC open and how much! (not now if blocked) and injects wrong, dead wrong. and floods. making what.
huge smog
and washing the rings with raw liquid fuel flushing off that clean oil, and huge start up wear, why not just leave it all working. or fix real problems.
we have these engines going 300k to 500,000 miles , easy, (w/clean oil)
why make it worse?> it's a great piece of engineering. (hacked)

it's not suffering, I PROMISE.!

that 2k ECT jump resistor lies to the ecu, causing it to go leaner, and wrong, the ECU has fuel evap tables that use ECT to use the correct vapor pressure, settings.
cold fuel does not vaporize. so going lean is not good,

there are many reasons for too rich cold.
1: low compression
2: bad fuel.
3: IAC bad, fails to close at 150f, or slow to get there. bad thermostat wrong therostat, or water line to iac blocked.
4: bad ECT
5; bad iat.
6:FPR bad,
7: fuel pressure not at spec,
8: its not the 02 its off line cold..
9: TV stuck open , tv cable not see with 10mm ply or some have 3 cables same, a/t, throttle and cruise
10: some bad guy attached the tv stop screw,(horror) he turned it and did you in.
11: ISC sticking open.
12: idle switch bad.
13: TPS calibrated wrong, see 12.
14 : injectors leak. do a leak down and a balance test yet on all 4?

how do you know it's too rich, sniff sniff? the scan tool wont tell you cold. how?


the cold start rpm is 100% a factor of engine block water temperatures, water. and the IAC opening rate
and not stated by you. what temp was the air outside and water temp, when experienced this rich event?
and how was the event detected?????

no lie IAC go bad.
and stick
or go non linear. just like a thermostat does and for exactly the same reasons, it's same technology
or sticky random.
or stuck open or stuck closed
and are hard to test.

so does FPR this old, many are, we see now.
http://www.fixkick.com
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#3
wow, wow and again wow!

first things first, THANKS a bunch for your time and effort in helping me.

i bought this car used in a bad shape and have done many things to tune it up (with very good success so far i think).

now, lets cut to the chase:

1.at +15Celcius, you think that an engine racing at 2300rpm is normal? because thats what mine did (it has ~200k miles on it) before i PARTIALLY blocked the IAC. now it cold starts at ~1500rpm rather than ~2300rpm.

2.regarding the 'rich event': it happened every time before i lied via the ECT. i could tell by my...nose! i literally could smeel unburnt fuel on cold starts for a few minutes. this effect was drastically reduced once i used that 2k ohm resistor. what it does (i know you know this already Wink ), is it makes the ECU think its about 35C instead of 15C. when on operating temps (85C), the difference between reality and ECT reporting temperature is minor to negligible (non-linear thermistor it is).

3.the reason i added the resistor is because i partially blocked the IAC (to compensate for the less air allowed). i am not sure (i need your input on this) what the ECU does in open-loop; especially on cold-starts. does it inject based on MAF input and ECT readings only? if yes, then why blocking (completely) the IAC makes the engine go rich? (since IAC is legal induction -MAF monitored). shouldn`t the ECU compensate automatically for a blocked IAC and spray less fuel?

4.yes, my injectors are the next thing i need to look upon. along with the FPR and valve lash. i have already ordered a gauge with an adapter to fit on the fuel rail line and check what the FPR (and fuel pump) is up to. my injectors look like nippon-denso brand and (desperately i think) could use some cleaning. just need to find some facility that does injectors in my area (not too easy).

5.my IAC closes completely right at 155F (measured with IR gun). Wink my thermostat is genuine suzuki 82C with CORRECT gasket ring (and some RTV Tongue). works like a charm. goes to operating temp within 3-5 minutes. upper rad hose doesn`t even get hot before thermostat goes to ~82C. very few thermal losses there. stock clutch fan discarded, SPAL 16" fan attached. fan switch (via relay to the fan) placed at top rad hose and opens at 90C (where the thermostat is almost wide open and the rad has gone hot -even down to the bottom). cluster temp gauge gets slightly above medium before fan kicks in and falls slight below medium when fan shuts off (~84C). fan never comes on even when cruising as slow as 40km/h (about 25mph). whole cooling system has been flushed 5 times within a week and fresh 50/50 coolant was filled. all gunk,debris and rust is out and gone. all large hoses are new.

6. spark plugs (NGK iridium), spark wires (Beru), dizzy cap and rotor (Bosch), cluster temp sender, radiator, heater core, hoses, thermostat, water pump, timing belt, suspension springs, shock absorbers, wheels & tires, and lots of other (smaller) bits were replaced with new ones, along with a complete brakes overhaul and lots of bodywork and painting.

what remains is transmission rebuilding (noise when neutral and on 3rd gear;must be a bad bearing(s) or worse), injectors`clean-up, FPR, and valve lash check-up. i also need to check that 17mm bolt on camshaft (do i even spell this properly?).
Reply
#4
welcome!

(04-25-2016, 06:09 AM)kthnos Wrote: wow, wow and again wow!

first things first, THANKS a bunch for your time and effort in helping me. You're Welcome !

i bought this car used in a bad shape and have done many things to tune it up (with very good success so far i think).

now, lets cut to the chase:

1.at +15Celcius,(59F, is this air or coolant temps")
you think that an engine racing at 2300rpm is normal? because that's what mine did (it has ~200k miles on it) before i PARTIALLY blocked the IAC. now it cold starts at ~1500rpm rather than ~2300rpm.
you blocked, the IAC thermal or IAC electric (ISC)???????????
the answer is 2300 is not normal at 15c Air temps. it's too fast. 1500 is normal and drops quicking and then totally as the IAC (thermal closes at 65C)
too fast idle cold and how ma



2.regarding the 'rich event':
happened every time before i lied via the ECT.
i could tell by my...nose! i literally could smell unburnt fuel on cold starts for a few minutes.
The cold CAT and cold engines, all make that smell due to the cold Air fuel mixture tables of the ECU.
usually you'd have to walk to rear of car, get nose next to end of tail pipe to notices this. (unless the wind blow it to the cab)




this effect was drastically reduced once i used that 2k ohm resistor. what it does (i know you know this already Wink ),
is it makes the ECU think its about 35C instead of 15C. (300 ohms is hot engine, and ECU exits cold start mode then exits warm start mode)
when on operating temps (85C),
the difference between reality and ECT reporting temperature is minor to negligible (non-linear thermistor it is).

3.the reason i added the resistor is because i partially blocked the IAC (to compensate for the less air allowed). i am not sure (i need your input on this) what the ECU does in open-loop; especially on cold-starts. does it inject based on MAF input and ECT readings only?
True: the maf works all the time, and is not all that accurate at low rpms, but cold starts are about 1500 rpm and maf works great there.
once engine warms and idle drops to 800 (IAC thermal closed 100% ) the 02 enters closed loop mode.. and now corrects MAF errors, (and some ECT)
this engine has no MAP sensor, so measures Air flows, direct (mass air flow senso)


if yes, then why blocking (completely) the IAC?(which one) makes the engine go rich? (since IAC is legal induction -MAF monitored). shouldn`t the ECU compensate automatically for a blocked IAC and spray less fuel? (sure but maybe not correctly)
great questions , when engine is in cold start mode (ECU) the ecu is not in closed loop. but is in TABLE mode.
the ECU looks up the temp then the maf reading , using the 2 axis table , finds which injector pulses are need, for regular petrol fuse , cold manifold, and engine, the tables go richer colder and are match for the PETROL spec.. on vaporization at all temps even to -40C. super rich there. crazy rich. there..
cold fuel does not vaporize, the tables are FUEL vapor tables. and are amazingly accurate, unlike any carb choke ever made.
and compensates for altitude too, EFI.
i think you are over working the problem. sorry, I which i know what your are troubleshooting. just sniff, or just 2300 or ??????

best is not to fool the ECU, make sure inputs are correct. first. (measure inputs)
wish i knew which IAC you blocked,? (both can be blocked) but which one, best is to called the wired IAC the ISC, for clarity.


4.yes, my injectors are the next thing i need to look upon. along with the FPR and valve lash. i have already ordered a gauge with an adapter to fit on the fuel rail line and check what the FPR (and fuel pump) is up to.
my injectors look like nippon-denso "ND" brand and (desperately i think) could use some cleaning.
just need to find some facility that does injectors in my area (not too easy). id just use the fuel pressure meter to test them.
The only risk is if all 4 are equally partially clogged, the all seem good, but most times one is bad. dead, weak or leaking. and bam you find that in the balance test. In not remove injectors if the tests pass, on my pump page. id not.
if the engine power is lacking at WOT, then id have the injector cleaned. lacking the full 95hp at fly wheel.
the balance test finds most of all the failure modes, (my 7 tests on my pump page and if from FSM too, id didnt invent it)
if those pass, it take 4 partial clogged injectors to fool, me and the full power of engine would be weak.


5.my IAC closes completely right at 155F (measured with IR gun). Wink GOOD, very near all mine. and is SPEC
what is HOt RPM, what is HOT ISC dutycycle, does the hot 800 rpm regulate? when you turn on head lights and blower? and hold 800rpm is this car a stick or auto trans?

my thermostat is genuine suzuki 82C with CORRECT gasket ring (and some RTV Tongue). works like a charm. goes to operating temp within 3-5 minutes. upper rad hose doesn`t even get hot before thermostat goes to ~82C. very few thermal losses there. stock clutch fan discarded, SPAL 16" fan attached. fan switch (via relay to the fan) placed at top rad hose and opens at 90C (where the thermostat is almost wide open and the rad has gone hot -even down to the bottom). cluster temp gauge gets slightly above medium before fan kicks in and falls slight below medium when fan shuts off (~84C). fan never comes on even when cruising as slow as 40km/h (about 25mph). whole cooling system has been flushed 5 times within a week and fresh 50/50 coolant was filled. all gunk,debris and rust is out and gone. all large hoses are new.
(all that is normal and prefect)


6. spark plugs (NGK iridium) )GAPPED to .70 mm?, spark wires (Beru), dizzy cap and rotor (Bosch),
this car has weak spark, do not run surface gap plugs, 2j,3j or 4j plugs run Iridium 1J gapped right, and its happy,
cluster temp sender, radiator, heater core, hoses, thermostat, water pump, timing belt, suspension springs, shock absorbers, wheels & tires, and lots of other (smaller) bits were replaced with new ones, along with a complete brakes overhaul and lots of bodywork and painting.

what remains is transmission rebuilding (noise when neutral and on 3rd gear;must be a bad bearing(s) or worse), injectors`clean-up, FPR, and valve lash check-up. i also need to check that 17mm bolt on camshaft (do i even spell this properly?).

vsig: year,G16B with 5speed sticK?, doors count? , 4wd or 2wd?
photo of engine? post it?


the G16b comes in many forms world wide,
different EGR
different intake manifold
some even have unique IAC /IsC s parts. (our IAC is under the throttle body bolted there) our ISC is on the front left plenum box and has only 2 wires)
be nice to see your engine, near the throttle body.


The 2300 prm cold start(if dash tacho is not fibbing) is too high for 60c starts (ambient and coolant temps)
most G16b the dash tacho, 1 line (1000) the idle is a hair above the 1 line. the dash tach is TOY GRADE ,and when old they lie. more.
i never trust it until i validate it with real tools (obd data) or hand laser tacho.(dead accurate)

if you block and air path, i'd need to know where. exactly. (suzuki changes parts names 3 times, so......)
you smell gas at cold start, maybe when you shut if off last, then one injector leaked down, all fuel drained there, and rail goes to 0psi.
then you start it later and sure it will be full of HC.(black smoke)

the injector leak down test is first. always if cold starts seem wrong.
it must hold for 1 minute, 25psi key'd off (test 3)
http://www.fixkick.com/INJECTORS/pump.html
fuel pressure must be in spec,
the FPR most work right keyon, idle and W.oT or the ecu will inject wrong.

what is the ect ohms at 60c, see my ECT page? "unplugged" 580 ohms is SPEC. what is yours.
http://www.fixkick.com/ECU/temp-sensors.html
what is maf voltage key on no start.
and then at hot idle?

the only hard tests are the INJ balance test. the 9v battery test is safe, i think, (lacking a real pulser tool)

when the FPR vac. hose is removed, does the nipple leak fuel, yes= bad FPR

more tests>?
sure
what is rpm HOT, engine, with the ISC hose pinched,(2 water are hot, 1 cold air hose, pinched.)
most do 400 rpm or even stalls.
this finds illegal air leaks,
or some one played with the idle duty screws (x2) or the TV stop screw VIOLATED by the unknowing.....
on our cars the old ISC internal rubber seat gets old and ugly and leaks air .. and can be cured, ask)

you have a scan tooL?

keep in mind I cant hear or see ,feel or drive car.
is engine misfiring,shaking or making odd sounds from dead cold or hot or driving?
got nice mag. spark wires, BOSCH mag,or NGK, is best. they last for a very long time and help make up for weak, spark, this EFI has.
mag is not carbon, not silicon, its coiled wire inside that are Conductors.
is the rear exhaust manifold tube cracked, as many do.? this has tin skins there, that must be removed to see this crack.

the FPR page is here, btw. overkill the on car tests are easy and enough.

http://www.fixkick.com/sensors/tests/FPress-reg1.html

what is hot rpm
is the CEL lamp glowing running'
if have scan tool and DTCs and are all sensor working
and is closed loop working hot.
is MPG ok>? petro/ per 100km.
http://www.fixkick.com
Reply
#5
G16b symptoms. (20 questions, so sorry )

the good bad and ugly?
cold idle speed too high (yes) is the TPS idle switch closed, and at 0v and not 5v, if 5v that means the TPS lost calibration
hot idle at 800 RPM (+-50) yes/no
if no, idle controls failing (long story here)
if yes 800, does hot idle hold at 800, as you turn on Head lamps, step on brake, turn on heater blower to high , defrost glass ON.
or shift to drive (a/t)???? if yes, idle regulation works. if not , not. (ask )

does engine misfire , cold ,warm or hot.
does engine hesitate driving, or bog, or bog then catch up.
does engine not have full power up hills
does engine shake, at idle, can you hear misfiring back firing or muffler explosions, or odd exhaust notes?
does engine make funny sounds.
Is engine still fitted with an EGR, is it closed at idle, at all times idle?
Does engine have a CAT. or is missing?
I cat dead? gutted or when hot , is the input same temp as output end? if yes, its dead cat and all dead cat cars stink first started or full time all the time, just less hot.

Are you running spark gaps at .7mm? (0.028") not at NGK factory .045" 1.2mm (it's the factory default, ) or any brand is like this.. and wrong.
cam belt not over 60k miles? 100km
crank pulley 17mm bolt at 94ft/lbs per TSB?
Got Bosch mag wires in the car or the NGK blue mag wires. mag wires, make any vitara a tiger, the stock spark is weak, so running MAG is SMART.
Never use carbon wire or silicon wire, ever. on these old cars. IMO
is static spark timing as correct spec, value, 8Degrees BTDC or per you cars spec, 5-8 are most. with the TIMING FREEZE jumper in place hot engine 800 rpm, is it? if set way advanced, the idle controls can fail.


ours runs 5deg, some are more. tad more.
http://www.fixkick.com/specs/Body-TAGS/h...age_9.html


this page cover all engine suzuki for timing freeze
http://www.fixkick.com/IGN_timing/IGN-FREEZE.HTML

and fails if the tps idle switch is not 0vdc.

have a scan tool?
is the CEL lamp no key, then out running?
Do you have OBD2 port above right knee, 16pin D-shell female? called OBD2 DLC port.? seen outside USA 1998 to 2001?


do you get say 8.4-liters per 100k economy on long drive. at moderate speeds.?

if engine misfires hot, does it stop with the 02 sensor (front) unplugged.?

is the maf at 1.0–1.6 volts key
then at idle hot.1.7–2.0 volts
then gun throttle hard and can hit 3v?

is hot ECT at 300 ohms, ?

at 60c, coolant is ohms at 580ohms, btw there are many wrong ECTs that fit the car but are dead wrong, check the ECT ohms with my table
to get the correct ECT takes a VIN code check.
our runs like this.
http://www.fixkick.com/ECU/temp-sensors.html

we also saw this 2 other ways
using the tech1 scan tool and others , and is set for European cars, the here it fails the ECT
but is because this scan tool has wrong plug-in for usa cars, that use a different ect. here.
there are 2 or 3 ECT used in Europe. but just 1 here. (16valves)
and one more tool we saw it repeat this problem.s
http://www.fixkick.com
Reply
#6
(04-26-2016, 12:06 AM)fixkick Wrote: welcome!

(04-25-2016, 06:09 AM)kthnos Wrote: wow, wow and again wow!

first things first, THANKS a bunch for your time and effort in helping me. You're Welcome !

i bought this car used in a bad shape and have done many things to tune it up (with very good success so far i think).

now, lets cut to the chase:

1.at +15Celcius,(59F, is this air or coolant temps") -> i think its both since its cold start at the morning. coolant temp = ~air temp.
you think that an engine racing at 2300rpm is normal? because that's what mine did (it has ~200k miles on it) before i PARTIALLY blocked the IAC. now it cold starts at ~1500rpm rather than ~2300rpm.
you blocked, the IAC thermal or IAC electric (ISC)???????????
the answer is 2300 is not normal at 15c Air temps. it's too fast. 1500 is normal and drops quicking and then totally as the IAC (thermal closes at 65C)
too fast idle cold and how ma

-> i blocked the thermal IAC PARTIALLY (not fully!) a little bit every time untill i got ~1500rpm cold starts (which i deem as 'normal'). i think my IAC pellet has gone loose over time (200k miles is no small number i guess).


2.regarding the 'rich event':
happened every time before i lied via the ECT.
i could tell by my...nose! i literally could smell unburnt fuel on cold starts for a few minutes.
The cold CAT and cold engines, all make that smell due to the cold Air fuel mixture tables of the ECU.
usually you'd have to walk to rear of car, get nose next to end of tail pipe to notices this. (unless the wind blow it to the cab)

-> i guess i have a flimsy nose then Tongue because i could tell from 10m away...



this effect was drastically reduced once i used that 2k ohm resistor. what it does (i know you know this already Wink ),
is it makes the ECU think its about 35C instead of 15C. (300 ohms is hot engine, and ECU exits cold start mode then exits warm start mode)
when on operating temps (85C),
the difference between reality and ECT reporting temperature is minor to negligible (non-linear thermistor it is).

3.the reason i added the resistor is because i partially blocked the IAC (to compensate for the less air allowed). i am not sure (i need your input on this) what the ECU does in open-loop; especially on cold-starts. does it inject based on MAF input and ECT readings only?
True: the maf works all the time, and is not all that accurate at low rpms, but cold starts are about 1500 rpm and maf works great there.
once engine warms and idle drops to 800 (IAC thermal closed 100% ) the 02 enters closed loop mode.. and now corrects MAF errors, (and some ECT)
this engine has no MAP sensor, so measures Air flows, direct (mass air flow senso)

-> in that case, since i get ~1500rpm cold idle (now, after what i `ve done), i guess its fine then? whats your opinion? am i getting too lean at cold startup with that 2k resistor?

if yes, then why blocking (completely) the IAC?(which one) makes the engine go rich? (since IAC is legal induction -MAF monitored). shouldn`t the ECU compensate automatically for a blocked IAC and spray less fuel? (sure but maybe not correctly)
great questions , when engine is in cold start mode (ECU) the ecu is not in closed loop. but is in TABLE mode.
the ECU looks up the temp then the maf reading , using the 2 axis table , finds which injector pulses are need, for regular petrol fuse , cold manifold, and engine, the tables go richer colder and are match for the PETROL spec.. on vaporization at all temps even to -40C. super rich there. crazy rich. there..
cold fuel does not vaporize, the tables are FUEL vapor tables. and are amazingly accurate, unlike any carb choke ever made.
and compensates for altitude too, EFI.
i think you are over working the problem. sorry, I which i know what your are troubleshooting. just sniff, or just 2300 or ??????

best is not to fool the ECU, make sure inputs are correct. first. (measure inputs)
wish i knew which IAC you blocked,? (both can be blocked) but which one, best is to called the wired IAC the ISC, for clarity.

-> i would NEVER block the ISC my friend. i am not that dumb Tongue plus, want idle controls on ECU when hot Wink

4.yes, my injectors are the next thing i need to look upon. along with the FPR and valve lash. i have already ordered a gauge with an adapter to fit on the fuel rail line and check what the FPR (and fuel pump) is up to.
my injectors look like nippon-denso "ND" brand and (desperately i think) could use some cleaning.
just need to find some facility that does injectors in my area (not too easy). id just use the fuel pressure meter to test them.
The only risk is if all 4 are equally partially clogged, the all seem good, but most times one is bad. dead, weak or leaking. and bam you find that in the balance test. In not remove injectors if the tests pass, on my pump page. id not.
if the engine power is lacking at WOT, then id have the injector cleaned. lacking the full 95hp at fly wheel.
the balance test finds most of all the failure modes, (my 7 tests on my pump page and if from FSM too, id didnt invent it)
if those pass, it take 4 partial clogged injectors to fool, me and the full power of engine would be weak.

-> i think thats the case (weak WOT) with mine, but i can`t be sure. but i will work it out one way (pump & FPR) or the other (injectors).

5.my IAC closes completely right at 155F (measured with IR gun). Wink GOOD, very near all mine. and is SPEC
what is HOt RPM, what is HOT ISC dutycycle, does the hot 800 rpm regulate? when you turn on head lights and blower? and hold 800rpm is this car a stick or auto trans?
-> its 5spd manual transmission. headlights and blower are not regulated via ISC i think. only power steering and AC. ~850rpm on hot idle always, unless i switch on the AC; then it jumps to 1000-1100rpm. endpoints on power steering also create an ISC compensation from what i can tell. i can even hear the ISC ticking then Wink
i had issues on HOT restart. interminent hot idle was 500rpm sometimes. didn`t happen again since i replaced the EGR. i think/believe that the spring on the old one was sticking sometimes causing it to not shut the diaphragm completely (one more piece of evidence was slight/audible pinging at idle when this happened).


my thermostat is genuine suzuki 82C with CORRECT gasket ring (and some RTV Tongue). works like a charm. goes to operating temp within 3-5 minutes. upper rad hose doesn`t even get hot before thermostat goes to ~82C. very few thermal losses there. stock clutch fan discarded, SPAL 16" fan attached. fan switch (via relay to the fan) placed at top rad hose and opens at 90C (where the thermostat is almost wide open and the rad has gone hot -even down to the bottom). cluster temp gauge gets slightly above medium before fan kicks in and falls slight below medium when fan shuts off (~84C). fan never comes on even when cruising as slow as 40km/h (about 25mph). whole cooling system has been flushed 5 times within a week and fresh 50/50 coolant was filled. all gunk,debris and rust is out and gone. all large hoses are new.
(all that is normal and prefect)


6. spark plugs (NGK iridium) )GAPPED to .70 mm?, spark wires (Beru), dizzy cap and rotor (Bosch),
this car has weak spark, do not run surface gap plugs, 2j,3j or 4j plugs run Iridium 1J gapped right, and its happy,
-> i will check my spark plugs box (don`t remember exactly the code now) and let you know. but i didn`t gape them at all.
cluster temp sender, radiator, heater core, hoses, thermostat, water pump, timing belt, suspension springs, shock absorbers, wheels & tires, and lots of other (smaller) bits were replaced with new ones, along with a complete brakes overhaul and lots of bodywork and painting.

what remains is transmission rebuilding (noise when neutral and on 3rd gear;must be a bad bearing(s) or worse), injectors`clean-up, FPR, and valve lash check-up. i also need to check that 17mm bolt on camshaft (do i even spell this properly?).

vsig: year,G16B with 5speed sticK?, doors count? , 4wd or 2wd?
photo of engine? post it?
-> check my signature Wink its G16BS with stick, 4wd, 5door.

the G16b comes in many forms world wide,
different EGR
different intake manifold
some even have unique IAC /IsC s parts. (our IAC is under the throttle body bolted there) our ISC is on the front left plenum box and has only 2 wires)
be nice to see your engine, near the throttle body.
-> thats exactly how mine is. check attached photo.

The 2300 prm cold start(if dash tacho is not fibbing) is too high for 60c starts (ambient and coolant temps)
most G16b the dash tacho, 1 line (1000) the idle is a hair above the 1 line. the dash tach is TOY GRADE ,and when old they lie. more.
i never trust it until i validate it with real tools (obd data) or hand laser tacho.(dead accurate)
-> i used a strobe light (when i adjusted spark advance). my tach reads ~100rpm lower than actual (actual=what the strobe light said and i trust it because it reads pulses on spark plug wire).

if you block and air path, i'd need to know where. exactly. (suzuki changes parts names 3 times, so......)
you smell gas at cold start, maybe when you shut if off last, then one injector leaked down, all fuel drained there, and rail goes to 0psi.
then you start it later and sure it will be full of HC.(black smoke)

the injector leak down test is first. always if cold starts seem wrong.
it must hold for 1 minute, 25psi key'd off (test 3)
http://www.fixkick.com/INJECTORS/pump.html
fuel pressure must be in spec,
the FPR most work right keyon, idle and W.oT or the ecu will inject wrong.
-> will do immediately once i receive the fuel pressure gauge and adapter that i have ordered. i will fit it on the fuel rail bolt. your site helped immensely on this! Wink

what is the ect ohms at 60c, see my ECT page? "unplugged" 580 ohms is SPEC. what is yours.
http://www.fixkick.com/ECU/temp-sensors.html
what is maf voltage key on no start.
and then at hot idle?
-> never measured the MAF, but i will do it if you think that i have to. ECT is spot on at ~260ohms @~85C.

the only hard tests are the INJ balance test. the 9v battery test is safe, i think, (lacking a real pulser tool)

when the FPR vac. hose is removed, does the nipple leak fuel, yes= bad FPR
-> thats an easy test. will do tonight!

more tests>?
sure
what is rpm HOT, engine, with the ISC hose pinched,(2 water are hot, 1 cold air hose, pinched.)
most do 400 rpm or even stalls.
-> mine is crumbling at ~300-350rpm when i do that.

this finds illegal air leaks,
or some one played with the idle duty screws (x2) or the TV stop screw VIOLATED by the unknowing.....
on our cars the old ISC internal rubber seat gets old and ugly and leaks air .. and can be cured, ask)

you have a scan tooL?
->no, but i will get one. i love wrenching this car!


keep in mind I cant hear or see ,feel or drive car.
is engine misfiring,shaking or making odd sounds from dead cold or hot or driving?
-> heavy shaking for about 2 seconds ONLY when cold starting ONLY on COLD winter mornings (+5Celcius) ONLY after i added the resistor Tongue

got nice mag. spark wires, BOSCH mag,or NGK, is best. they last for a very long time and help make up for weak, spark, this EFI has.
mag is not carbon, not silicon, its coiled wire inside that are Conductors.
is the rear exhaust manifold tube cracked, as many do.? this has tin skins there, that must be removed to see this crack.
-> my exhaust gasket was leaking and i got i replaced. didn`t notice any (visible) cracks on the exhaust manifold. catalyst however may be EOL since it was never replaced. i guess a smog test will see that (soon to be done).

the FPR page is here, btw. overkill the on car tests are easy and enough.

http://www.fixkick.com/sensors/tests/FPress-reg1.html

what is hot rpm
is the CEL lamp glowing running'
if have scan tool and DTCs and are all sensor working
and is closed loop working hot.
is MPG ok>? petro/ per 100km.
-> constantly around ~8.7L/100km and thats ALL with short city trips (5km) so the engine just reaches operating temp by the time i switch off the car.
no CEL problems (i had issues when i got the car with VSS and Oxygen, but i sorted these out for good).

   
Vitara 1998, 1.6L/16v, 5door, 5speed, G16BS.
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#7
ok , it's got good mileage figures, so can't be too sick
the isc hose pinch looks good.
ok your strobe lights like mine, can dial back and see real rpm (that tool is dead accurate,digital , is reasons. good.
the plugs must be gapped to .7mm this old car has weak spark, not till the COPs, (later ) did spark go high energy,
yours is like ours but has the Electric EGR, motor drive EGR< way better than our Vacuum modulated monster.
good.
that 2300 rpm not 1200 to 1500 rpm seems to be all from the IAC< so it must be old and non linear, but does close at 65c so works there,
just opens too far, when open. finding one is not easy.... (cheap)
i think rockauto.com but are expensive.

10 meters away stink.
sounds like its way to rich cold started, maybe the FPR is messed up or stuck closed, but if it was MPG would suffer.
i agree that is a big big stink.... not just random whiff of dead cold cat sink.... as is normal. (till it lights off)

sure we only block isc (sorry, not implying full time ) to test them, only and related's, to see if its a contributor to the high cold idle.
how did you modify the IAC, , really curious that.
its a huge path in the base of TB. to the horn.
any blockage attempts on the IAC would be very hard to do. like go 90% to get a flow reduction

here it is
how'd you do this....
at 19"hg vacuum , huge air flows here. cold.

[Image: 16v_IAC_w1.JPG]

or at the horn end (the huge slot in the TB horn?)


the cold start air is:
IAC + (nothing from ISC ) + air bleed top of TB + TV (zero flow here, all the time at idle)
the bleed screw sets idle dutycycle to 50% (centers it)

also the ISC can leak a bit old.(its rubber ring seat )
ive even tightened it (isc 5mm allen) a hair to cure this leak (i blown in it with lips, feel the leak hose off, key off, and then if it leaks tighten this hex screw. to stop it, just a tad. do not let the spring inside compress....

also the TB top, bleed screw might be way wrong.
if the bleed leaks air all the time to calibrate the duty cycle but if someone unscrewed it CW, and duty is now way off hot. then cold idle will suffer.
hot duty is 50%
if if its way off due to bleed wrong this leakage for sure will mess up the IACs flow, and add to it more than normal (50% duty calibrated)
when cold the ecu keeps the ISC 100% closed, and must not leak.
http://www.fixkick.com
Reply
#8
ok, spark plugs are NGK IFR6J11 (again, i did NOT gap them in any way). please let me know if this is ok!

regarding the IAC, check the attached picture. i downloaded it from your site.

now the point is the engine shacking at cold-cold startups. you think its misfiring or what?

btw, i can barely blow air within the ISC when its closed. and i cut a new paper gasket as well.

   

oops! just checked NGK site. my spark plugs are 1.1mm gap. OOPS!
will i have problems with that gap? should this really be 0.7mm? are you sure?
Vitara 1998, 1.6L/16v, 5door, 5speed, G16BS.
Reply
#9
spark plugs
they do not make spark plugs for 10,000 engines.
only heat ranges and size and reach. (and metals)
the gap is set by the factory machine (computer controlled) that sets the all near 0.045" 1.2mm and are used on 100s if not 1000s if different engines
your gaps are wrong.
and they NGK or other do not guarantee any factory gap, at all. (oem plugs , not magic snake oil , no gap plugs. aka , surface fire and all that )
i even have and email from them stating that.

Did you look it up. all g16s here run .7mm all do, because the coil is not a HIGH energy coil. it's just weak. and the gap must be lower.
on new cars with hot red hot high current coils, x4, x6 and x8 COP'S run huge gaps. 1.2mm works, to allow this but if a turbo the gaps shrink again, due to the huge pressures under boost. (what the do is balance combustion pressure to spark energy) with due care.
but your engine, has old weak coil 1 coil and cap ,rotor and long long wires. the spark is weak. (by today's standards)
on ours the hood sticker shows lash gap and spark plug gap;. in full view.
as seen here
http://www.fixkick.com/specs/Body-TAGS/h...age_9.html

here is an international listing for tune up data.
http://www.fixkick.com/specs/tuneup.pdf

Real suzuki FSM books spec them from 0.028 to 0.032 , (the true spec)
all shops use the lower number, why? , because they all wear wider so, set it low. and let it run longer,
wider gaps will cause hard to start car cold, and under huge engine loads, (hills)

if your induction coil is located on the fire wall or in the distributor, ours in the distrib and is weak. both are.
to get high energy ignition , it takes huge primary currents, and these cars don't get that until 1999.
and j20 engines up. with COPS. 4 cops. each engine and huge ignitor currents.


shacking is always misfiring, can be bad spark, flooding misfire, or injection issues. and even low compression.
each shake is a combustion failure, part or total. misfiring.
the gaps matter when cold and rich it needs narrow, spark gap to make it more powerful. (intense) to fire it rich.
our operators guide chapter 19
[Image: 3_25_04_16_4_32_51.jpeg]


I'm not sure where that other hole show in your photo goes, in the TB bell horn , left ? is that IAC path 2?

ok the IAC was rolled way back with restrictions. that would do it , for sure..
some TB may have just 1 slot,, IIRC...
http://www.fixkick.com
Reply
#10
well...i guess that could possibly explain my shacking engine on really cold startups in the winter...
will gap them this week! thanks a lot!

regarding the IAC path 2, no its not. it just goes to the frame. i need to investigate what the heck is it.
Vitara 1998, 1.6L/16v, 5door, 5speed, G16BS.
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