98 GAGT; C/E Lite, ABS Lite, Eng Stutter

:banghead:
Ok, I have a Pontiac Grand Am GT with 64K miles. Almost 2 years ago the heater core went bad and the guy we had working on it bypassed the core until a new one came in. Car ran extreemely hot but he said it was ok but just to be careful. We drove it sparingly for the last year and a half and have just begun to get back to work on it. Took it to the shop and they did the D/T and it had a misfire in one of the cyls. Did a compression test and it was LOW! We worked it a little more and it started to run better but all of a sudden it started to sputter and miss at idle...under load...on accel...everywhere. You'd think I had put a high performance cam in from the sound and shake. The ABS light comes on from time to time and the check engine light is on almost constantly. Now, going back a few weeks before it started to sputter, the ABS light and the check engine light went out...but now they are both back on. When you get on the gas and need to accel quickly, the check engine light will blink. We have given her a tune up, changes the air filter, o2 sensor, ran cleaner through the tank and system and we had the fuel filter and pump about 3 years ago. So to sum it up... engine stutters under any conditions but seems to "catch up" at times while driving and then falls back off, ABS light on constantly, Check Engine light on constantly and blinks when acceleration. I am tellin' ya guys, this thing is driving me :screwy: so if you can give me any help (or even your :2cents: worth) I would appreciate it. So would my wife, she's tired if hearing me :swear:!

Welcome to AF, and the check engine lite code is? The abs should be scanned with an abs functional scanner for codes and comparative wheel speed sensor inputs. Was the cyl with low compression the same one as the code referred to, what was done to fix that. Lots of info missing here.

The Check Engine Code came up oxygen sensor, even after we changed it. I am going to take it to the shop this weekend and have them re-run it. Since I am stationed in Italy and must rely (for the most part) on our Auto Skills Shop, I'll need to contact them about an ABS Scan, although the light went out today but as sure as the sun would rise it came back on just before we got back to the house. As for the low compression vs. misfire, the diag. never showed a misfire (it showed a bad o2 sensor) just some rough idle/engine shake which led me to believe it was a misfire, even one of the guys at our Auto Skills Shop said the same thing and could hardly believe it when they didnt get a misfire reading. I told that the mounts will have to be replaced due to the movement of the engine. I thought that it might be the head gasket but there is no smoke (on occasion when it is hard to start thereis some smoke but not much). It has also been suggested that it could be a bad valve. To me it feels like it is not hitting on all 4. Simmilar to when the timing is off but there are times when it picks it up and goes...then again at the same speed & same conditions it runs rough. I am sure that this isn't enough info but let me know what you need and I will get as much info as I can.

Again what cylinder had low compression and what was done to correct it?

it was the number 3 and to date, nothing has been done. We tried some engine restore to see if that would help.