My 85 IROC has suddenly developed an extremely annoying problem. First, it is much harder starting than it used to be. I have to crank the engine for several seconds before it will fire. Once it does fire, it idles very rough, almost like it's missing, or perhaps like it's flooded. Upon acceleration, the roughness only intensifies until I level off at cruising speed, whatever that might be. When I step on it, the symptoms return until such time as it levels off again.

When my car was new and under warranty, I had to have all 8 injectors replaced because one or more were fouled. The dealership told me that there was a problem with the fuel manufactured at that time, and that they were having problems all across the country with the TPI engines. This was when I lived in Texas and they had to search all over the place to find the injectors. They finally found some in Florida and had them over-nighted to repair my car. The symptoms the car showed then are very similar to the symptoms it has now. I'm taking it to the shop on Tuesday. Does anyone have any experience with this particular problem? Does anyone have any experience with power flushing injectors? What other reasons could be creating this type of behavior?

Would appreciate any help.

 

Yes, I have experience with "power flushing" the injectors. It's a waste of time. I had my '86 injectors "cleaned" by the MotorVac process several years ago, when the car had only 18,000 miles. It ran just about as badly as it did before the overpriced service. The next year before I took it out of storage I removed the injectors and sent them for a proper injector cleaning and flow-matching. It hadn't run that well since it was new. I wouldn't even bother with an on-car "cleaning" service, since the only thing which gets cleaned out is the wallet.