Formula94lt1

My car sat for 8-9 months while i did a lot of work to it. Battery was disconnected the entire time. I did a timing belt and rearend work. My car runs very rich now, so rich I can't really drive it and it blows smoke. Does this sound like stuck injectors? I have 2 cans of sea foam in the tank and there is only about 6-10 gallons in it.

When I start it, it starts immediatley and searches for a stable idle bounding up and down from a few hundred to 1200 rpm for about 5 seconds then it settles and becomes a little rough and smokes a lot. Adding throttle makes it chug a bit and it take considerable throttle to increase rpms compared ot normal. It will rev but it almost dies when it returns to idle and never stops smoking. It isnt oil either as it smells of gasoline strongly.

I checked the dampers and reg and no leaks. Temp II is good so is air intake temp sensor. I adjusted the maf, which gave me no issues before it sat, back to 382ohm from 578ohm, but I dont think this would totally dump fuel. If this is stuck injectors will this blow over with forced driving? I am out of time working on this thing by the end of this weekend and to be honest absolutely sick of working on it.



I didnt expect 8-9 months to effect it like this. Crankcase smells of gas.

Rob Edwards

Maybe this is the reason? The solution to pollution is dilution.

SeanR

Sorry I missed your call Chris, was under a car.

I didn't know you had that much SF in the tank. It's going to be one clean engine LOL

Formula94lt1

When sea foam is run through the intake it makes a lot of smoke, when run through the gas tank you can have a lot in there and it wont smoke and certainly wont make the car run rich and smell like gas is vomiting out of the exhaust. Ive done this on a previous car with no adverse effects.

Larry Velk

A vacuum leak makes a 32V run very odd. If you put in an '87 FPR (higher pressure) you may want to set MAF ohms to lower than ~380. My '86 liked a leaner MAF with the higher pressure regulator - ran OK at ~380, ran very good with the screw backed out some.
You said you did work on it - go over everything again.

Formula94lt1

Spark is all good Sean, how hard is it to remove the rails with the injectors still attached and watch if they leak when I prime the pump? Plenums are all I need to remover right?

John Speake

Could be MAF. Remove airfilter, switch on igntion without starting engine, and see if the hot wire is glowing orange/red... best do this in a darkened place.

If it glows orange/red then MAF has failed with a thermal runaway problem.

JHowell37

Your injectors aren't the problem.

SeanR

We had a car two weeks ago that had a very similar issue running wise. Smelled like it was a fuel issue, excessive fuel. The problem was two injectors were not firing. Now why it smelled so bad when 2 were not working right? I don't know, but once new injectors were installed, the issue went away.

Imo000

did you touch anyting on the intake while working on the car? Is the vacuum line to the trans (if it's auto) still hooked up?

VehiGAZ

Sounds like my LH failure symptoms it absolutely stunk of unburned fuel, didn't hold idle, and chugged when the gas pedal was prodded.

That said, my LH failure opened the injectors and kept them open. My mech diagnosed this symptom with a noid light - simple and easy.

I'm a big fan of Sea Foam!! Tune-up in a can...

Formula94lt1

I will check the maf for glowing now, didnt touch any intake stuff besides the plenum and air box, and its a manual trans.

As far as LH failure, I guess thats possible. It will hold an idle if left alone though, only when you start the car and if you prod the throttle does it act like and sometimes doesnt, hold an idle.

I find it strange though that any of the problems besides injectors could have come about with the battery unpluged and the car just sitting though.

VehiGAZ

Sounds MAF-y then. Good luck!!

76FJ55

I think what happens when you have dead injector is that the O2 sees excess air in the exhaust due the lack of combustion in the effected cylinders. O2 sensors work off the oxygen potential difference between the outside of the exhaust and the inside of the exhaust. They could care less about any amount of fuel, excess or insufficient. So the O2 loop tells the computer there is too much Oxygen in the exhaust, the computer interprets this as lean and adds pulse width to the injector timing, which causes the functioning cylinders to go rich and pump excess fuel out the exhaust. At the same time the nonfunctioning cylinders are still supplying the exhaust stream with unburned oxygen so the O2 loop still thinks the system is running in a lean condition. No matter how much fuel trim is added the end result is the lean indication is always there even though the functioning cyclinders are running in an excessively rich condition.

SeanR

Thanks for that, makes perfect sense.