E36 Running Rough (just bought)

[Troy911]

Okay , hopefully someone can help me out, the other day I bought a 1992 E36 5 speed with 157K on the motor. The motor is running rough at when you take off , it holds an idol but hesitates through out the rpms, but still has some power . No check engine is coming on.

The girl I bought it from said she took it to car wash and the car stopped running, her garage took out the DME and due to it getting wet , dried it out and put it back in. She drove it home and parked it due to it not running right. This was last Jaunary.

Two days ago I test drive it and the Muffler sounds like it is about to fall off and is very loud, I took it home changed the fuel filter, took all the coil packs out and found #4 was blown out , it poped ! , I got a used one and put it in. I also made sure all the oil was out of everywhere in and around the plugs and boots. Also changed the oil and filter and air cleaner, RUNS the Same.

Tomorrow I'm getting a used stock muffler and putting it on, I think this will help it run better, what do you guys think should I just get a new computer for it ? I think that might be the problem but not sure and dont want to spend $250 for one .

Let me know what you think.

[jwfuller]

congrats on the purchase.

Are you getting hesitation throughout the RPMs, or does it stop when you reach a certain RPM? Do you know it is the engine doing it, or are you feeling vibrations through the shifter/center console/under your seat?

Also, does the engine vibrate some at idle?

The typical response to vibration at idle and hesitation at lower RPMs is a sensor out of whack, typically an O2 sensor. Being as your muffler is really loud, some hole might be interfering with the operation of the O2 sensor, which would throw your timing out of whack. Do you know how to do the stomp test to pull your OBD codes?

Since you were in there pulling spark plugs, there is a small chance that you didn't torque them down enough, and they are vibrating and setting off the #1/#2 or #3/#4 knock sensor. The plugs should be torqued to right at 18 lbs. No more, no less.

After the obvious is corrected, I would suspect also that the DME might have a wire loose going in to it. The garage may have not hooked it up correctly. I don't know much about it or how its wires work. Somebody on here may stop by and mention more.

[TOTALLYBMW]

If the ECU got wet and the car is not running right it's better to at least try and check how the car is running with another one plugged in, maybe one borrowed from a breaker's yard?

[TOTALLYBMW]

Another thing, if you check and that coil pack has popped again, it is a sure sign of something wrong with the ECU (computer).