Pontiac Repair: bad running quad 4, compression issue, regulater

Question
i have a 88 grand am with a 2.3L quad 4 eng. about 2 months ago it started cutting out while driving the more i drove it the worser it got so my machanic changed the coil pack and it was fine run like new. befor he fixed it i thought it was the fuil pump so i changed it and the filter and that was then now its doing the same thing again so i changed the coil packs with new ones and changed the coil carage ( battle ship ) new plug ends and plugs it still not right then i changed the fuil rail and injeckters and fuil regulater and $300.00 later still runs bad can anyone tell me what to do next and does it have a egr valve i cant find one on the engine thank you

Answer
Hi Glenn:

well it can be a lot of things. looks like you covered the bases a bit. No this engine doesn't have a EGR valve. It would check for spark on all 4 cylinders with a spark checker. it's a pain to do on this engine being that the coils are inside the cover assembly. Then check for injector pulse on all 4 cyliners. Fuel pressure on this engine is the the area of 35-40 PSi. Check that as well. Lastly check the compression on all 4 cylinders. it's going to be one of the things I mentioned here. I would lean more towards a spark issue or possabaly a low compression issue Maybe the timing chain may have jumped? Does the engine have any kind of noise comming to the timing cover area when it's running? If so that is a sure sign that the timing may have jumped. good luck :)