A Number of Fun Issues!

[Garemie]

Hey fixkick,

I bring you a tough one... I hope you like it.

1994 Sidekick 16v in Samurai. Federal emissions.

Will not idle hot. I have checked for vacuum leaks, nothing I can find. I assume its an EGR related issue. When it's able to run, (very low rpm, probably 3-400) and I try the EGR stall test, there is no response.

I have tried another EGR that I know is good. Still no response for stall test. I also cleaned out the passage way pretty damn well.

There was a Check Engine light before I had to remove battery, but it hasn't come back and it's been a couple days.


Where should I start for diagnosis?

[Perry]

Hi,

I might be able to get you started on some issues. I'm facing similar issues on my 1998, the fuel pressure regulator is next on my list, because it fails rich resulting in a stinky, stalky bumpy idle hot.

I also want to tell you the Check engine light is your friend. Try not to reset it unless you have checked to see what it is trying to say. As I'm sure fixkick will tell you, something is wrong when it comes on and we want to find out why. Check out this video, the first 2 mintures to find your codes without a reader. You'll want to get the CRL back and read it before you start throwing parts. It will just be a crap shoot without it.

http://www.fixkick.com/CEL/DLC/DiagJump.html. <<<<obd page

[fixkick]

welcome !

Hey fixkick,

I bring you a tough one... I hope you like it.
is this a stock engine? many sammi are not. now... long ago engine swapped.

1994 Sidekick 16v in Samurai. Federal emissions. G16b engine, 4 injectors? or 1 injector??????[/color]

Will not idle hot. (low rpm only, ?>) HOt or cold, , cold will be like 1500 , is it?)
I have checked for vacuum leaks, nothing I can find. (vacuum leaks cause IDLE way too high on G16a, on G16b low due to MAF by passing causes)
I assume its an EGR related issue. (if the valve is closed, its not this cause it only needs t0 close, EGR is inactive at idle , on all G16s)
do you have power loss? (if yes check sparking timing of huge retard, cam belt slipped, or check compression for huge drop, 150psi normal , 80 not, same cause.

When it's able to run, (very low rpm, probably 3-400) and I try the EGR stall test, there is no response.
The EGR exhaust path is probably 100% blocked, and is not it.
if an engine ever can run at 300, most will not, and you opened the EGR it must stall instantly. or the EGR is dead, but is a distraction here. all this EGR
worry, egr closed is what we want at idle, (the ECU defeats it at idle )

I have tried another EGR that I know is good. Still no response for stall test. (if the valve diaphragm ring moves open 1/4" then closes with finger then that main EGR valve is ok
I also cleaned out the passage way pretty damn well. (head tunnel too>? and exhaust port for egr?) path is long... but lets fix the real problem
you can drive great with no EGR at all. and is a great test to prove that, defeated, shows even runs great with no EGR.
then when engine is no running great, fix egr to pass smog or to get longer life of exhuast valves (they run cooler last longer) and CAT more happy. (NOX reductions)

There was a Check Engine light before I had to remove battery, but it hasn't come back and it's been a couple days.(my guess code 51 egr dead)



Where should I start for diagnosis?

fix RPM hot idle, 800 is spec, 400 is crazy low.

i do spark timing ony because its a 5min job. if retarded the cam belt slipped as all do over 60,k miles.
or do compression.

post both good bad and ugly
what does the car do driven. good or bad. both.
has full power?
misfires at cruise.
bogs
hesitates
overheats
the full story on driving, and even coming to a stop helps.
EGR love to stick open coming to a stop. (the idle switch closes, , egr is CUT dead, if it sticks open engine stalls or goes to 1/2 normal RPM)

[fixkick]

you have this G13 engine? this is stock setup you have this TBI engine G13, just like this schematic shows>?
http://fixkick.com/sammi-stuff/late-sammi-efi-94.jpg

This TBI engine always races with vacuum leaks, (that means all leaks in excess of ISC controls (authority) results in racing idle, hot. 800 +-50rpm is spec (750 to 850) is ECU job to keep it here.
In idle up mode, (idleup pin on ecu active,the RPM goes near 1000. for many things(PS overload,Head lamps on, heater fan on, defrost fan on, AC/on)
a small leak does not do that, that is because a working ISC closes and hides said leak.
400 rpm is 1/2 normal (is a warning something is very very wrong)
low idle has many causes, huge actually
1:; someone set spark timing way off. or did so for below.
2: cam belt slipped
3: Gross engine misfire. (bad spark?)
4: EGR stuck open, if closed its not this.
gross power loss. for many reasons, misfire, low compression (see#2) low fuel pressure, clogged TBI injector, clogged fuel filter (in both cases partial clogs)
5: gross power loss, CAT melted.
6: map dead, (rare as hens teeth) but hose can fail to it, easy, vacuum hoses,even seen them melt, the rubber in hose goes to gooey, and collapses.
7 : engine never gets to 180f and floods
8: ECT bad. lies to engine, and tells engine engine is cold when is 180F. or more.
9: a dead ISC only causes, wrong RPM at idle,never loss of engine power. (it does other things but are while driving, like anti next snap mode, when lifting foot off throttle fast)

sounds daunting right?,. sure, but is only a few tests with tools and gauges.

[fixkick]

btw all engines (G) misfire at 300 RPM, its not called misfire here, this is normal. RPM is wrong, that is abnormal.
idle low can be hacking caused.

1: someone played with distributor timing
2: or played with TBI screws, say turned the stop screw wrong. on our TBI , it has bleed screw, that can be set wrong (closed clockwise max or turn fully ccw)
have a photo of your TBI? (throttle body)

[Garemie]

welcome !

Hey fixkick,

I bring you a tough one... I hope you like it.
is this a stock engine? many sammi are not. now... long ago engine swapped.

I put this motor in my Samurai myself. It has ran good for quite some time, this idle issue is new. It is a 1988 Samurai with a 1994 Sidekick 16v G16A 4 injectors

1994 Sidekick 16v in Samurai. Federal emissions. G16b engine, 4 injectors? or 1 injector??????[/color]

G16A - 4 injectors

Will not idle hot. (low rpm only, ?>) HOt or cold, , cold will be like 1500 , is it?)

Cold idle is proper. Starts at around 2000 for a few seconds, then drops to around 1500...then when its hot it goes to 800 and slowly goes down till it either dies or runs like a tractor at 300 or so RPM.
I have checked for vacuum leaks, nothing I can find. (vacuum leaks cause IDLE way too high on G16a, on G16b low due to MAF by passing causes)
I assume its an EGR related issue. (if the valve is closed, its not this cause it only needs t0 close, EGR is inactive at idle , on all G16s)
do you have power loss? (if yes check sparking timing of huge retard, cam belt slipped, or check compression for huge drop, 150psi normal , 80 not, same cause.

It was running perfect idle yesterday and I was able to do a proper timing adjustment using freeze timing. Is still good.

When it's able to run, (very low rpm, probably 3-400) and I try the EGR stall test, there is no response.
The EGR exhaust path is probably 100% blocked, and is not it.
if an engine ever can run at 300, most will not, and you opened the EGR it must stall instantly. or the EGR is dead, but is a distraction here. all this EGR
worry, egr closed is what we want at idle, (the ECU defeats it at idle )

I have tried another EGR that I know is good. Still no response for stall test. (if the valve diaphragm ring moves open 1/4" then closes with finger then that main EGR valve is ok
I also cleaned out the passage way pretty damn well. (head tunnel too>? and exhaust port for egr?) path is long... but lets fix the real problem
you can drive great with no EGR at all. and is a great test to prove that, defeated, shows even runs great with no EGR.
then when engine is no running great, fix egr to pass smog or to get longer life of exhuast valves (they run cooler last longer) and CAT more happy. (NOX reductions)

There was a Check Engine light before I had to remove battery, but it hasn't come back and it's been a couple days.(my guess code 51 egr dead)



Where should I start for diagnosis?

fix RPM hot idle, 800 is spec, 400 is crazy low.

i do spark timing ony because its a 5min job. if retarded the cam belt slipped as all do over 60,k miles.
or do compression.

post both good bad and ugly
what does the car do driven. good or bad. both.

Runs like a top at any speed. Maybe a slight power loss from before.

has full power?

Yes....or maybe 90% of full power...which is why I guess EGR??
misfires at cruise.
No
bogs
No
hesitates
No
overheats
No
the full story on driving, and even coming to a stop helps.
EGR love to stick open coming to a stop. (the idle switch closes, , egr is CUT dead, if it sticks open engine stalls or goes to 1/2 normal RPM)

---

you have this G13 engine? this is stock setup you have this TBI engine G13, just like this schematic shows>?
http://fixkick.com/sammi-stuff/late-sammi-efi-94.jpg

Its a G16A 4 injector from a '94 Sidekick.

This TBI engine always races with vacuum leaks, (that means all leaks in excess of ISC controls (authority) results in racing idle, hot. 800 +-50rpm is spec (750 to 850) is ECU job to keep it here.
In idle up mode, (idleup pin on ecu active,the RPM goes near 1000. for many things(PS overload,Head lamps on, heater fan on, defrost fan on, AC/on)
a small leak does not do that, that is because a working ISC closes and hides said leak.
400 rpm is 1/2 normal (is a warning something is very very wrong)
low idle has many causes, huge actually
1:; someone set spark timing way off. or did so for below.
2: cam belt slipped
3: Gross engine misfire. (bad spark?)
4: EGR stuck open, if closed its not this.
gross power loss. for many reasons, misfire, low compression (see#2) low fuel pressure, clogged TBI injector, clogged fuel filter (in both cases partial clogs)
5: gross power loss, CAT melted.
6: map dead, (rare as hens teeth) but hose can fail to it, easy, vacuum hoses,even seen them melt, the rubber in hose goes to gooey, and collapses.
7 : engine never gets to 180f and floods
8: ECT bad. lies to engine, and tells engine engine is cold when is 180F. or more.
9: a dead ISC only causes, wrong RPM at idle,never loss of engine power. (it does other things but are while driving, like anti next snap mode, when lifting foot off throttle fast)

sounds daunting right?,. sure, but is only a few tests with tools and gauges.

[Garemie]

So where do I start for not idling?

[fixkick]

Virtual Signature: 1994 Sidekick 16v G16b 4 MPI injectors (in a Samurai body car) my guess 5 speed. FrankenSammi.
is the check engine lamp on key ?
is the check engine lamp off running
is the Check engine lamp flashing code 12 , idling , and driving? (DLC diagnostic jumper inserted)??????????? this is first. and not stated yet.+

Low RPM
Low , are you parked, sure, are you in gear, ? Automatic trans, ? or is this a Stick shift car, ive now idea what you have or swapped in to that sammi.
what is there now, fully, 2door 4wd, with what exact drive train, (transmission?)
is this with or with out the Sidekick harnesses for engine, and speedo cluster, dash harness sets ????
Is this car using the 95sidekick ECU?

keep in mind my my answers may be different for stock 95 Sidekick than any Samurai.
Btw, the EGR is turned off at idle and WOT. By ECU command. so it can not effect WOT ever, unless its sticks open.
if the EGR main is closed at idle, then it can NOT be ECU caused, simple tests show that. (hand testing EGR main)

what can low idle be (basics) ? its only 2, answers
1: The ECU can not control idle. (huge list of causes)
2: The engine is running super lean, at idle.

If we had a scan tool we'd see that #2 is false,but you dont have that. so must guess. (or add propane gas to the air intake, and see if it speeds up)

so what causes #1.

Gross misfiring, heard, seen or felt.
super rich fuel mixture, causing misfire.
ISC dead. (for many reasons, but dead, it is idle controls are now Dead.)
idle switch not closed, cause ISC to be off line. dead.
injectors leaking, or clogged, causing misfire. and lower rpm, all misfire can and will cause too low RPM if the ISC can not , correct it.
air leaks, all air leaks can cause lean AFR, air fuel ratio mix to go lean, all air leaks bypass the MAF and so that makes the MAF reading low. causing lean.
stated above as #2 cause.
Air leaks are complex on MPI, any leak or many leaks from the intake valves to the back side of the MAF are all illegal leaks.
and illegal leak is called Unmetered air flow, air not measured by the MAF, and not corrected by the O2 sensors.


keep in mind we are working with no scan tools here.
so must work blind or use meters and scopes to find what is failing, guessing can be hard, lacking no evidence at all but (too low idle)

is the ISC clean. (I remove it,(leave hoses connected so water dont leak) then clean it, then test it with a 12vdc battery, (it uses 1amp current) and is seen to do this , and heard in this first video.... if this fails, the ISC is dead.

http://www.fixkick.com/videos/FLV-all/showtime.html#ISC


it really is not tough one, its just testing engines with no scan tool is super labor intensive, (the whole reason we invented OBD is to avoid that)
are the spark tips running white or jet black? that is a test too.
does the propane tests show engine is lean?
at idle what is the MAF output voltage.?
does it idle at 800 HOT with the o2 sensor unplugged?
does the ECT read near 300 ohms unplugged, hot?


I do have a whole list of tests. to find out if its lean cause, too rich caused, or ISC dead. and more.
each test is a manual test using hands, tools and meters, to find out that all sensors are working
to discover if the engine is running lean or rich, and to see if there are air leaks.


is only one , spark plug black (tips) and injector might be leaking
is fuel pressure at spec? if at 55psi all 4 will over inject and go rich and misfire and idle controls cant correct RPm to 800. so fails.
see how important it is to know what AFR is doing at IDLE? rich or lean?
one other cause , sure
the front 02 sensors, if you have any exhaust leaks NEAR there, the 02 sensor slams 0volts, and the AFR goes super rich, before 1996, its worse.
this causes sparks to go black, engine misfires and idle fails. (low)

to learn all this, one must do tests, (no scan tools, lots and lots of tests) this is called collecting evidence.
the evidence at hand, tells the tech what direction to go and the next set of test.
case in points:
1: too rich we do too rich tests.
2; too lean we do too lean test.
3: isc dead, only, we do more tests related to ISC,


A scan tool tells use all 3 in 5minutes flat. and more, lots more, it shows the readings of all sensor.
ECT reads wrong
IAT reads wrong
O2 reads wrong
idle speed, wrong, and target speed 800 correct.
idle switch stuck open (wrong)
long term fuel trim set way lean but lean never happens (or the opposite)
closed loop never happens at idle.

basically we do the tests by hand , lacking the scan tool. by hand means (gauges,meters , scope at hand, mechanics have all these tools)
learn to read spark tips.?
when idle fails (stuck low)
1: is engine heard to misfire, see it shake, feel it shake, bingo misfiring.
if you move the throttle, by hand just a tiny bit does idle rise easy, ? or does it fight you.
2: key off engine, pull spark plugs, are they white or black. (oldest engine test on earth over 100 years old. this test ,called reading spark plugs)
3: pull ISC off left side of intake air plenum box, is the valve free, means moves 1/4" easy with say a tooth pick tickling it? clean it yet?


The ISC has to suck in EGR+PCV black cloud of death (nasty mess) and loves to clog. up.
its what i call a gunk cloud, that is a simple clean and test,
The ISC and EGR valve both love to clog on all these G16 engines.
that's it
ive listed most tests, and can expand on each, if you need it.

good luck !

[Garemie]

You have given me a lot to work with.

I will start on this tomorrow.


If it helps, the car runs fine with what seems to be full power at any speed on the road.