air intake (heated vs non-heated) and IAC bypass

[fixkick]

the biggest challenge
is seeing if its obd1 or 2
and what dutycycle mode the DLC uses. (harder) much harder.
THE DLC on many old suzuki's used a special meter that runs a non standard current mode to test this.
the later its a voltage mimic, mode pin, converts duty to a voltage from 0 to battery voltage., where 7v equals 50% duty hot.
what i uses is a meter that measures the ISC directly, and scales duty in the real world, 200 hz signal. (this automotive DMM has a mode called duty)
if the duty is way off, say the bleed screw is set way off, then the cold start will race, if the screw is too far CCW.

as seen here
this is just very simple air bleed. it is common to be set wrong, when a mech. finds idle speed wrong, its gets played with. (wrongly)
http://www.fixkick.com/IDLE-AIR/Slide_Sh...ge_31.html

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what it does, is puts the ISC in the center of its range.
steps. i use are.
1: make sure isc does not leak, unplugged elect conn.
2: make sure TV does not leak a drop of air. it's 99.9% closed, (the no touch screw, not touched,. LOL)
3: no vacuum leaks. even the brake booster can leak and causes problems,. (i dont think you do)
4: at this time the only air flowing cold engine, are IAC , and bleed .
5: start engine, get it hot and IAC closes and only air is ISC (modulated no) and bleed
6: make sure idle is at 800.
spark timing is set to spec. (using the freeze pin 4(blu-red) on the DLC) and idle switch is closed (pin2) and at 0v...never 5v at idle.
7: connect duty meter up to DLC . (or scope, to ISC direct, or duty meter to ISC direct) (there are 3 or 4 ways to connect, one works)
8: turn bleed for 50% duty,
9: done

on our 1998 dlc pin 6 (purple) reads 7v at 50% , the older cars, this pin is useless due to custom Suzuki only meter works, in current mode.

http://www.fixkick.com/IDLE-AIR/dutycycl...html#Begin

the other hard part is finding the DLC, ours have 2. that year.
the one under hood, can be in 3 places.. (most are 6pins)
R/F head light shell (our 98 is here) has a black rubber cap to protect unused pins.
front of battery
or left front strut tower.


with duty set correct
there will be less air flowing on cold starts. because the bleed adds to cold air starts.

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if not,? the IAC is bad. (now runs too much air cold)

[fixkick]

g16's dont shake cold or hot, they do not.
unless it's misfiring and that is not normal at all.
it for sure is NOT THE IAC doing that, faster idles actually burns better ! extra air , better.
if compression good.
lash good.
egr not stuck open (its new and not)
spark timed, at spec, (freeze jump set)
plugs at .7mm spec, not at NGK factory setting, ever.
MAG wires, are a huge value here, hot spark always is on all Otto cycles engines.,
if that is good, then it has fueling issues , purely, not air issues.

i tend to think (magic crystal ball) that its leaking injectors. but no proof yet, just that black cloud over the car.

if on a hot engine rap the MAF with back side of screw driver, if rpm changes, maf has serious problems.
gently.

here is my live driving map plots 1 of 3 on my maf page
this is real. from my 96 scanner, and dumped in to MS Excel.
http://www.fixkick.com/my96-16v/MAF-TPS.JPG

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in the end we do fuel pressure test over 10 of them.
the ECU on this car does not monitor pressure nor correct for it.
it just injects wrong when pressure is wrong. (o2 tries to cure it sure but 02 is dead, accelerating)

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we are working 2 separate issues,
misfire
and bad idle cold. (races, not stalling)
so seems confusing , but is not.

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misfire usually causes stalls.
if present,, and never racing, ever.

[kthnos]

g16's dont shake cold or hot, they do not.
-> mine started doing this only after i added the 2k resistor. only at really cold mornings though.


unless it's misfiring and that is not normal at all.
it for sure is NOT THE IAC doing that, faster idles actually burns better ! extra air , better.
if compression good.

lash good.
-> valve lash will be checked thursday morning. i will get back to you with the results.


egr not stuck open (its new and not)
->definately not a problem now. it used to, but the new EGR solved those issues for good.

spark timed, at spec, (freeze jump set)
->spark timing is at 8 degrees. i know spec is 5, but we have RON95 fuel here. which allows 8 degrees easily i think.

plugs at .7mm spec, not at NGK factory setting, ever.
->gaps are wrong at mine. will be fixed definately on thursday morning as well.


MAG wires, are a huge value here, hot spark always is on all Otto cycles engines.,
->my wires are Beru. its a good brand (germany) as far as i hear around. i wanted NGK but they were out of stock at the time.

if that is good, then it has fueling issues , purely, not air issues.

i tend to think (magic crystal ball) that its leaking injectors. but no proof yet, just that black cloud over the car.
->injectors will be cleaned within the next month. i found a local guy but i need to see his equipment by myself. otherwise i will have to travel 100km to another city to do them.

if on a hot engine rap the MAF with back side of screw driver, if rpm changes, maf has serious problems.
gently.
->no such issues with my MAF.

here is my live driving map plots 1 of 3 on my maf page
this is real. from my 96 scanner, and dumped in to MS Excel.
http://www.fixkick.com/my96-16v/MAF-TPS.JPG

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in the end we do fuel pressure test over 10 of them.
the ECU on this car does not monitor pressure nor correct for it.
it just injects wrong when pressure is wrong. (o2 tries to cure it sure but 02 is dead, accelerating)

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we are working 2 separate issues,
misfire
and bad idle cold. (races, not stalling)
-> i think bad idle at cold was cured. its at 1500rpm now. and hot idle is at 850rpm (or 750rpm with headlights on).


so seems confusing , but is not.

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misfire usually causes stalls.
if present,, and never racing, ever.

[fixkick]

seem idle regulation is not happening
best is to turn on all accessories at once, hot idle. (not A/C)
the rpm sags say 100 or less and corrects in 1sec, to 800, corrects to before rpm. before big elect. loads.
I do HL, brakes and blower at one fell swoop.. on 5sp. (left hand, right hand and stomp) rpm can twitch down and correct..
if it drops, then the ISC is not regulating, check idle switch first. goal is max load on alternator.fast and see results of RPM changes.
The ecu watches rpm like a hawk and if does. open the isc real fast. (if awake)


the 2000 ohms causes ECU to see hotter coolant, so would go leaner. 60c water shows 68c water (lied) this should be trivial change .
2000 across 580 =450ohms.
not a big change at all but at 0c it be huge lie. 0c reads 45c, huge change and vastly leaner.

[kthnos]

it does compensate/regulate for AC and power steering though. definately does that.
headlights,blower,defroster, anything else does not cause regulating though. never actually tried all of these together (to see the reaction), but if i turn on just one at a time, there is a slight (just slight) rpm drop and no compensation. again, AC and PS excluded, there is always a reaction to these.

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the 2000 ohms causes ECU to see hotter coolant, so would go leaner. 60c water shows 68c water (lied) this should be trivial change .
2000 across 580 =450ohms.
not a big change at all but at 0c it be huge lie. 0c reads 45c, huge change and vastly leaner.

on one for the coldest mornings here (~12C) i measured my ECT @3.5k ohms. with the 2k at parallel, the ECU should think its about 36C. sure, its a lie, agreed. but on operating temp (~85C), the lie is only a couple of degrees C. which (i think) is negligible.
the point is, (leaving aside smog and such) is it safe for the engine (exhaust valves anyone? ) to run lean when cold? its a 5 minute warmup, not too long, but still... you think i am stretching anything here?

[fixkick]

ok, seems it's only slow. the isc, basically the rpm le just sags down a tad then,the back to 800 in 1 second. (its programmed to hold 800 rpm,)
P/s overload and a/c. are unique modes,.yes.
is the idle switch at 0vdc? tps pin 2?
its a cold engine and the AFR (air fuel ratio ) is super rich cold (those tables,) so all you are doing is moving from less, too rich.) its not harmful.
what if the fuel pressure was wrong?
the richness, is a table, the maf points (and ect) in to the table and the tables cold are, pure petrol evap rates, very well known and super accurate they are.
so knowing that, if its too rich then the injectors are injection to rich, and can be only 2 things. (besides limphome mode)
1: ECU inputs wrong,
2: fuel pressure wrong, (too high)
3: injectors leak.
when you get it fixed, you will not want to play with 2000 ohm ect resistors, ever, it just runs sweet off the tables cold ,it does.
the exh valves are protected when needed most, at full load hot up hill, the egr is flowing and valves are kept cool (and NOX abated on the side)
all else runs cool valve. for sure cold starts.

[kthnos]

never checked the TPS for calibration status. but my guess is that since its holding ~850rpm (and boosting to ~1000rpm with AC on), it should be fine.
then again, i lose nothing by testing /back-probing. will do!

by the way, i checked the FPR vacuum hose. no signs of fuel there. i also received my fuel pressure gauge (and adapter) to fit in the fuel rail line, so tomorrow i will have a better picture on whats going on with the FPR (pump,leak tests,etc).

now, i have a question regarding the injectors: (yes, i did read the relative page on your site ).
-lets assume one of the injectors is leaking. is this fix-able with cleaning/back-flushing and replacing the o-rings? or if an injector is leaking you just find a replacement?

[fixkick]

the injectors might clean out
with a Chevron techron, fuel injector cleaner, in the tank, its the most powerful sold (has benzene as a cleaner/solvent)
im not for addtives but this one ok and easy to do.
if the injectors leak here i send them here.

there is a fuel rail kit too, tank ,hose to rail and runs car and small tank uses a commercial grade cleaner.
http://www.witchhunter.com/
or the like, (geography)

injectors new are expensive
many stores sell rebuilds. (with exchanged core.)
the 2 o-rings
if one cracks, suck air to the intake tunnel.
if other cracks , engine gets wet in fuel and fire time.
the injectors have 10 micron screens, and can only be cleaned back flushed, and with ultra sound, best of best way per link above,. read his page. its good.

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if pin 2 sits at 0v each flip of throttle, keyon, not running?
it's OK
blue-white wire, back probed.
http://www.fixkick.com/sensors/tests/MPI-TSP1.jpg

super easy test. 0v good, crack throttle 1mm, open and the pins jumps to 5v. the idle switch.

[kthnos]

still haven`t tested the TPS yet.

BUT, i gaped the spark plugs to 0.7mm as you (and suzuki ) recommended.

i also had my valve lash checked up. it was HORROR my friend. 0 lash on all valves! PO must have been drunk or had a (permanently) drunk car technician or something. i `ve set them to 0.15mm (intake) and 0.17mm (exhaust) after i left the engine to cool down for more than 1 hour.

i am not sure if i am seeing things or not, but i have the feeling i have slightly better throttle response now (after gaping the plugs and setting the lash).

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and new valve cover gasket as well. i hope this one will not leak.

[fixkick]

0 lash can burn valve fast, glad you found it !!! great discovery .
some think car has HLA. and does a brain fart.
can be set Mr. otto cycle way, TDC firing each cyl. or the suzuki short cut way, im sure you saw that trick. in the FSM.
it will run better, for longer,
hot spark is very important under load. and the owns you have are the bees knees. (super good)
the felpro never leaks,,,,, i promise.... really good fit an great base materials. there.