SEARCHED! YES SPENT AN HOUR pouring over the search function. Similar problems found but no answers.

Ok i can tweak out the lumpy idle at normal operating temperature the car will run fantastic and idle normally durring the time i drive it.

Then.....I go into the store for 10 mins come out and guess what the car goes to....well lets just say it revs 800-1100rpms to no avail.....

So i hop out after it reaches operating temp again and adjust the tps back to smooth it out... It's a loosing battle, (it's a NEW DEALER TPS) i thought it was bad so i replaced it. Well the problem is still here. and i adjust the stupid thing every time i drive it...I have listened for vac leaks and have found none....

Please give me a list of things to do to fix the problem

I am running really rich, lumpy idle and terrible gas miliage, plus the car is putting from the exhaust like this rrr pop rrrpop pop rrpoprrrrrrrrrrpop. yes the plugs are fouled but untill i fix the rich running issue i am not spending another $38 a set untill i figure out how to fix that. Is there a mixture screww or something. I am running rediculaously rich.. it's a 87 se BTW.

 

Have your injectors cleaned recently? Vac leaks make the car run lean generally. Air filter clogged? Have you checked the resistance on your TPS at all once it's set to a position it 'likes', as to when it's bouncing?

 

Have you tried using the ISC and the var resistor/air mix screw to smooth out your idle?

 

The only screws i have touched are the one on the top of the tb ( idle set screw right) and the tps adjust screw... Where are the other adjustment screws at? ISC and resistor mix?

 

the idle mix one is near the AFM on around the passanger strut area (it's got some screwy jb weld looking crap ontop of it so you can't 'adjust' it)

 

can't adjust.........hmmm. Is there anything i can adjust?

 

Well, you can remove that crap they put ontop of it and adjust it, should have specified a little better, just said that so you could identify it a bit easier.

 

...

 

The idle mix screw has potting in it, so the adjustment locks in place. It should only need to be readjusted when you do major maintenance to the car. The ISC is the initial set connector. It needs to be jumpered whenever you tamper with your idle mix settings.

 

ok...i am way out of my league here....The car has had a very recent rebuild and i am working out the bugss.....like 3-4k old....

 

Your not out of your league man, all this is outlined in the FSM!

 

My thoughts:


- forget about listening for vac leaks. Grab a garden hose and use it to go from one vac hose to the next, and also slowly go over the manifolds. SLOWLY. Unlike using carb cleaner, using a garden hose is free and the water won't sit on your hoses and eat them... Keep in mind that vac leaks also occur at joints and conections going into the block. The last vac leak I had took forever to find - turned out to be a bad rubber insulator between a primary injector and the block...


- don't be afraid of using the idle mix screw. I've used it and so has my mechanic on his own GSL-SE and nothing's come of it. It was just the only way to get our idles down where we wanted them. Adjusting that screw will not send your motor into a fit.


- follow the FSM procedure for setting your idle -> use a jumper in the specified plug by the leading coil or you're wasting your time.


I think you've got a vac leak. Hopefully, that's all it is, cuz it's usually a cheap fix.

 

UPDATE- I set the TPS and had the injectors cleaned, this solved the problem. thanks