Hey hope someone can point me in a good direction. Got a 90 z28 five speed tpi car that has a fuel pressure issue. The car is getting way too much fuel. At first it was smoking like crazy white smoke. I thought maybe head gaskets at the time but I took it to a mechanic and he worked on it and diagnosed it as excess fuel not coolant smoke. He had it for awhile and really didn’t do anything to fix it. He ended up putting e85 in it and that stopped the smoking. So my question is what would be telling the car to push so much fuel? Is it a regulatory issue or is something telling the computer incorrect info that it’s pushing the fuel in like it this is super cold out or something. I’ve heard that happening to a coworker. The mechanic didn’t want to waste time on a old car.... thanks

 

White smoke seems like a coolant in the oil issue to me...I would check it and make sure it has no coolant in the oil. Does it smoke all the time? Does the exhaust smell of fuel?

On the off chance it’s not coolant related but fuel the coolant temp sensor can cause the engine to think it’s very cold and dump excessive fuel. A obd1 blue tooth data scan app can tell you what the sensor is telling the ECM. A fuel pressure gauge would also be useful when working on these cars. Also dump that “mechanic” and find a better one.

 

If it's extra fuel, the car will run terribly and be low on power all the time.

If it's blown (or in the process of blowing out) headgaskets, you'll get crazy white smoke on startup that goes away when the engine heats up and it'll run almost like normal.

 

Yes it did smoke all the time especially when giving it throttle it would fill the yard. It did not smell like coolant and did of gas. He put the e85 in and the smoke went away but now the tank is almost empty and the ratio of e85 to gas is less and it’s smokes again. I had to increase the idle to get it to run but after that it’s not that bad. So the air intake temp sensor wouldn’t be a culprit just maybe the engine temp sensor?? The fans do not want to come on had to wire them in to a switch

also it’s getting hard to find mechanics with tools for these older cars. Sean’s like they like the new cars that self diagnose themselves. Got a84 ho cutlass with controlled carb and no one has the tools to diagnose a similar issue. Does oReilly have a obd1 scan tool to rent if you know

thanks