I have an 88 grand prix with a 2.8. It starts and idles fine, but as soon as I start to open the trottle the engine stumbles and dies. It will restart and idle fine. I have had the MAP, MASS, TPS sensors replaced. Fuel filter and fuel pump replaced. Converter has been flow checked and is OK. Any help on which direction to head next woulb be appreciated.

ses? what is the exact number? did you replace those trying to fix this problem?

Can't offer a thing regards that engine, but man, that problem is identical to the one I had with my ride. It was the ICM, at least with mine. Good luck, the guys here are fast with help.

By process of elimination you are pretty much down an ignition coil or the ignition control module. Plugs and wires (which you did not mention) could give you a misfire, but your engine is stalling which leads me to believe that is not the problem.

Is the CEL lit?

This is my aunt,* vehicle. I did not replace them but she had a couple of local mechanics work on it and so far that is what they have replaced. At first the CEL was not on. Now it is flashing and the engine won't start at all. I scaned for codes and got a code 45. Fuel pressure is good. If this was a non ECM vehicle the symptoms say fuel problem. With all the parts that have been replaced , I am starting to think ignition module also.

try unplugging the maf and see if it starts

I will try that. I am going to work on it as I can this week. Trying to schedule it in. I don't have much free time except on weekends.