Hello all. First time here, but I have found quite a bit of info on my 2.4L on here. But, I am afraid I need to ask a question.

I have a 96 Grand Am with the LD9 2.4L that had 202k on it. It jumped time and bent some valves, and after checking the head, it was also cracked. So, after letting the car sit a few years, I found a good engine from a 97 Grand Am that only had 133k on it. Before I swapped it into the car, I put a new water pump on it and checked the timing. Anyway, I put a brand new fuel pump in it and fired it up. It starts and runs just fine, until it slows to normal idle. It then starts to miss. I have gotten the random misfire code, and have checked compression (195 psi or so on all 4 cylinders) and have checked for vacuum leaks, but can't come up with anything. I swapped the ignition module (boots and all) from another one that runs fine, and that didn't help either. I've checked for corrosion on the grounds and such too. it seems to run fine down the road and accelerates like it seems like it should. So, any ideas on what the miss would be? It also has a new FPR and fuel pressure tests good.

The other question I have is this. After messing with this car for a while, I have noticed it is getting a sort of clattering sound that almost sounds like it's coming from the top end. When it's cold, it is really bad, and if you blip the throttle and when it's dropping back to idle, it almost sounds like the timing chain is hitting the side of the case for a second and then it quits when it gets back to idle. Any ideas on this? Thanks guys!

I've had misfire problems on both of my 1996 2.4K Cavalier convertibles over the years. Replacing the (white) ignition coil housing, coils, spark plugs, and boots fixed the problem. See the following link and skip down to the post that says, "SOLVED".

My wife's 2.4L sounds a bit clackety, like a diesel engine-- even after I had my mechanic replace the timing-chain tensioners when replacing the water pump. It has sounded that way for many, many years.