chugging/lopping at idle

[cjrecker]

I have a 1997 Grand Am SE with the 2.4L Twin Cam engine. My husband is driving himself crazy trying to figure out why the engine is chugging or lopping at an idle. He's changed all the sensors, spark plugs, fuel rail, injectors and I don't know what else. It only does it at an idle and the car shakes, but does not quit. He's going to change the computer also to see if that takes care of the problem. This is a car I got from a friend with a set up engine and my husband got a used engine and put it in. Also, the ABS braking system seems to take over when you let up on the accelerator and the tach jumps up and down between 1000 and 1500 rpm's. Any advice would be appreciated. I love the car otherwise. I used to own a 1986 Grand Am and loved it too.
Thank you.

P.S. Did all 97's come with the remote unlock? I didn't get one with mine.

[fluffybunny]

im guessing you mean its missing? check the coils, do you have a check engine light? and you said your husband swapped a used engine in it? it could be a number of things then..... it is just going to come down to weeding out and tuning till it comes out right........check the motor mounts..... and no, not all came with remotes......its obdII though so it should be able to have remotes programmed for it though. the tach could be a bad sensor.

[cjrecker]

I think he checked the coils, but I'll ask him. The engine light is on and when the diagnostic computer is put to it, all it says is: It's missing. Duh! We knew that already. It doesn't say what to check though. The tach jumps because of the ABS braking system kicking in. Could the ABS thing be a bad sensor too? I didn't need the remote, I was just curious as to if they all came with them. Thank you for all your help.