MY 90 5.7 TPI has a cold I think. When I start it when its cold, she runs great....or seems to anyway. But when it warms up, it seems like its missing, or hunting. I replaced the O2 sensor, the IAC valve, TPS, coil, cap & rotor, and its still not right. It seems to be running rich too. When I pulled off the vacuum line off the EGR and started the car, it has NO vacuum when cold or hot. So does this mean my EGR valve is messed up or my EGR valve solonoid is bad? I dont understand how to use a meter to check for volts....I need some help here guys........thanks

 

maybe the EGR valve and line is fouled up with carbon.

 

I pulled the line off the EGR and solonoid and blew it out. Also, took plenium off and I can sqeeze the diapram on the EGR......seems a little tough to press.....but that doesnt mean its not broken right?

 

Iam not trying to deterr you away from here but have what about putting it on a scanner and see whats going. Your gonna be chasing your tail with a problem like that. There are a lot of things that can cause our TPI engines to run like crap like that.

 

I brought it to a GM dealer........and they charged me $80 for 10 minutes of scanning. They said I needed a TPS because at one time there was a code 22 and it wasnt a hard code.......but my light never came on and I know the light works. They also told me it could be any of several things, but they couldnt tell me what it could be because they said the older computers do not get detailed as far as telling you what it is that is wrong.........so now Im spending money I dont have to try and fix this problem. Im willing to hear any suggestions.....Im so dam lost in this crap.........Im guessing its either the EGR valve, and/ or EGR valve solonoid. Also.....When I changed my cap and rotor.........everything below the rotor was pure rust. Im wondering if that is the problem here......isnt that the distributor itself? Could that be the problem with it being all rusted and coroded? Thanks

 

oh yeah........could anybody tell me what it is NOT for sure.....being the car runs great until it warms up........it sputters/miss throughout the RPM range, runs rich and backfires a little when I blip the gas at higher RPMs....not always....but maybe half the time. The dealership told me it might be a bad injector...but wouldnt that mean the car would run like crap even when first started? Also....when I taped on the EGR valve with a screwdrver......it ran better longer than before I tapped it......maybe coinecodence? I dont know

 

well now that you say that there is a lot of rust under the cap, I would look into changing out the module. You may be getting electrical resistance in the module as it warms up. And even if that is not your problem, it certainly isnt helping things at all. At one time, Autozone use to testmodules when you brought them in. Not sure if they stil do it. Pull you cap backoff and correct anything inside there that doesnt look right. You may have to pull the entire dizzy out to make the job easier on you but then you open up a can of worms trying to put the dizzy back in ifs its your first time. My best advice on removing the dizzy is to first make a mark with a marker on something under the hood i.e firewall, plenum etc, that the rotor is pointing to. This will be your reference point for re installing the dizzy. once you make that mark you can then pull out the dizzy. if you buy a new module, make sure you apply the contact goo between the module and base.

 

thanks....I will look into that.......what is a dizzy? how much do you think the module is and what about the other rust after I change the module....will it be ok?

 

dizzy is short for distributor. The module will cost about $35. I would try and remove as much rust as possible. If the dizzy is far from looking somewhat usable, then I would suggest getting a new one. Autozone has them for about $100. I know you dont want to hear all this but thats how it goes with our cars.

 

thanks.....Im not sure what would be considered usable or non usable, but its real bad....believe me. Even the really thin paper material on the pick up coil is falling apart..........I think its the pick up coil....its the thing just below the rotor..........but non the less.....the rust is VERY bad...........thanks for your advice man....I really appreciate ya..... Now........all I need to do is find out where everybody meets and mingles with their cars......Im in Huntington Indiana.......about 70 miles north of Indy and about a hour and a half south of MI........

 

if the rust is real bad then dont eve bother trying to restore it. Get a new one and get peace of mind that you now have a brand new dist.

 

yeah......I think your right.......where is a good place to get a good one? Do I have to get one from a GM dealership or do I go with a after market one? Thanks......also......will the new distributor come with a new pick up coil and module?

 

Proform sells a distributor for about $150 and it should come complete with everything yo uneed to install it. Try and look for a dist. that already has everything in it and willplug directly into your stock plugs. Either Proform or GM or even Autozone will be about the cheapest you will find them at. The aftermarket ones get a little pricey. try browsing the jegs or summit site and see what you find.