Not sure if It's in the wrong forum or not sorry
I got a trouble since 3 months and I can't find a way to fix it. This is driving me insane ! If I cant find what's wrong, I'll throw it off a cliff ...
Symptoms have started 2 or 3 days before low coolant appears, due to a leaky water pump that have been fixed, but this crap is still goin' on.
Check engine : Too rich code (this is pretty helpy ...)
Rough and jumping idle and driving is harsh too
Black smoke coming out from the exhaust pipes
Engine stalling at very low speed
VERY low fuel economy
No performance at all, engine's running at a higher rpm to conpensate i guess
Hard start at cold, I need to press it to the floor to start it, easier to start when warm or hot.
Radiator fan always On even when cold and dont stop until keys are removed

Sparkplugs has been changed, wires are goods,coils has been changed,cracks in the WAI has been fixed and new air filter has been putted on,vac lines have been checked for cracks or bent, ECT sensor has been replaced,IAC valve and TB has been cleaned,Injectors have ben checked everything seems ok,no fuel sipping from the FPR vac line. Injectors cleaner has been put in the tank too...
I KNOW then engine is surely running hell ova rich but can't find a way to fix it. Next step is the O2 sensor and a clogged cat...
Some on here have great ideas, so please let me knows.

O2 sensor may be bad. Black smoke is the clue.
dennis

black smoke: too much fuel. system too rich: too much fuel. poor gas mileage: too much fuel. car stalling at an idle/need to hold it open to start it cold: too much fuel.


did you check the TPS? hows your fuel pressure? how were the injectors checked? were they flow-benched? what did the plugs look like when you pulled them out?



JBO Stickers! Get yours today!

the TPS has been checked and seems to work fine. Fuel pressure hasnt been checked, tough. Injector #3 leak by the outside and the orings has been swapped with the Gm kit one without succes,still leaking... I swapped the #3 injector with a used one with no change. Others injectors "look" to be workin' fine,though. Sparkplugs were carbonised on the tread and the #3 one has the half of the tip covered with black soot?Sooth..They were replaced by brand new ones and they are now carbonised too. Everything's logic, knowing that the engine is run way too rich ...I just can't find an easy way to test leaking or bad injectors myself.
I'm a pretty DIY guy but kinda new to injection and troubleshooting.

Btw, swapping the O2 sensor is useless, since the sensor is ignored by the pcm at startup...From what I've read.

Sounds to me like leaking injector(s). Do the ohv's have a test port on the rail? If so, turn the key to the run position with your gauge hooked up, don't start it. Then turn the key off after a few seconds. Look to see if the pressure drops when you turn it off.

Sometimes I read that fuel injector replacement should be a part of a major tune up, about every 80 to 100 thousand miles.

I guess you could...I would have them serviced(cleaned)

ok thanks for the info. I'll look into that. Since I can't afford news ones (cheaper place here is asking 150$ CN...). Maybe someone know if an exterior injector leak can lead to an inside leak? Since the 3 others seems to be ok. #1 has ben changed for a brand new one 2 years ago.

I don't know a whole lot yet, and I need to check my FPR too, but couldn't the FPR be stuck mostly open or mostly closed and not even have a leaky diaphragm?
and how did you check for fuel at the FPR vacuum line?

Here is a video of someone who noticed fuel att he FPR vacuum line, but only after longer than a minute.
I need to check my FPR too, but need the mechanic to do this, I don't know if fuel could suddenly gush out, be careful.

Quite interestind I must say, I'll tchek it out tomorrow.

I think this test is on a return type of regulator.
As far as a return regulator, I think the 97 2.2liter does have one but be careful as usual, I'm not a professional mechanic
Here is a question for you or anyone, is there a pressure fitting somewhere that you know of to test the fuel pressure easily with a hand held fuel pressure gauge?
Not that I have one, but just good to know.

There might be a vacuum test also, but how much vacuum to apply I don't know, it might be a test
where you apply vacuum to the regulator (with the engine off?) and see if it holds the vacuum for a certain number of minutes? Or is this actually
the p.s.i fuel line pressure test that I'm thinking of?

You are correct. Give it like 20 in hg of vac. And see if it holds it for a few minutes. If you can get your fuel rail out, just take it off the manifold, with the fuel lines hooked up, and injectors still on the rail and turn the key to the on position and look for fuel leaking out of the injectors.

The 2.2 doesn't have a fuel pressure diagnostic port. I have actually cut my fuel line and put a "T" fitting in it for my nitrous system. If you really need to check fuel pressures you can cut the rubber line, just be careful and watch for any leakage once your splice has been repaired. Also check the readings of your map sensor. see If the vacuum is reading correct at Idle. how do your brakes feel? If they feel hard or more tough when you are braking you may have a torn diaphragm in your brake booster. pull the large vacuum line from the booster and plug it off and see if that helps the running rich issue.

Vacuum leak would cause lean condition, not rich. It blows my mind that they would not put a service port on the fuel system. Stupid Gm

Dave De Stefano wrote:Vacuum leak would cause lean condition, not rich. It blows my mind that they would not put a service port on the fuel system. Stupid Gm

can you explain this? I was under the impression that the fuel pressure regulator is vacuum controlled on these engines. as the engine is accelerated manifold vacuum decreases, acting on the fuel pressure regulator to release/close the diaphragm to stop return flow to the tank. this increases the rail pressure, correlating to an increase of injection pressure.

if the vacuum line from the throttle body is cracked, damaged, or removed, the vacuum source is lost and the regulator would be at full pressure, dumping excessive fuel into the cylinders even at times of high manifold vacuum (idle), eventually destroying the catalytic converter

or am I wrong?

Maybe it depends on where it's leaking vacuum.
Also have you cleaned your fuel system?

Update - All the firing system has been replaced including sparkplugs, wires,coils. Pcm has been tested and OK, Relays,fuses ,etc are all OK. ECT sensor is been replaced too. Battery has been replaced due to the previous owner who dosnt put the right terminal bolt on it and the terminal itself of the battery has been damaged. Now I got a pounding sub, +1 for me. Leaky injector #3 has been replaced for a brand new one and now it don't leaks anymore! but I'm still having the same issue.

BUT now I have a code, P0325 -> Knock sensor. Code was erased with a scanner and the code comes again every time, causing the coolant fan to run all the time, and stop if the cell is cleared. EVERYTHING that can cause the trouble has been swapped over. I'm pretty sure the KS is bad (I guess, IT MUST BE this...) Knock sensor's gonna be replaced during the week. Someone know if the sensor can be replace by the wheel well? Doing the job by under is now impossible since the exhaust line is in 2 1/4 pipes and I got an auto trans, so my hand even can't reach the oil filter (PITA to do the oil change by replacing the oil filter by the throttle body btw).
Car is running pretty bad at startup...Lack of power and high fuel comsuption is killing me ! This is really pissing me off. Thanks for the support lol.

I forgot to mention that every vac leaks is been repaired. Fuel components hasnt been touched, though. Fuel filter is been replaced 4 years ago.

The fuel filter needs to be changed about every year, and the fuel system also needs cleaning.

Ok I'll take the fuel filter in consideration. How the fuel system is supposed to be cleaned ?

Just a suggestion but i have the same problem changin my oil..i have a 2in midpipe...iv been changin mine by takin the pass. side wheel off and theres a whole just big enough for my hand and u can pull the filter right out.....its way easier than the old way from under the car

Nice ! Thanks for the info.Oil change is due this week-ends

your welcome.i feel the pain...literally...as a ohv owner

lol I don't know why but I can't junk my ohv for the life of me...My J has never left me on the side of the road in the last 4 years New fuel filter this week-ends too. I'll keep u posted.

btw what symtoms is the car having now...i read what all u had changed but is it doin the same as before?...when u first started this i was gonna say i think its 02 sensor..mine did the same terrible gas milage,poor excelleration and even stalling...changed the 02 and made it alot better...but a week after i did it my head gasket started leaking...after that its been runnin like a champ.lol