Engine Misfire on 93 325IS

[LeeV]

I appologize now i am a newbie to BMW's.

I replaced all the injectors and the plugs on this car so far and it still misfires. Ran it on a computer and brought up no codes, has good compression in all cyl. and I just cant figure this one out.

PLease anyone with any help i need to get this fixed fast, I am thinking maybe exhaust leak?

It runs strong above 3K but idles rough and takes off like a dog.

thank you for your help, Lee Vanhorn

[bpddaddy]

Lee, that sounds like it could be a vaccum leak or an intake manifold gasket. But remember, I'm just guessing. Have you checked for leaks? Spray carb cleaner around the intake manifold.

Additionally, the "take off like a dog" - fuel pressure check? Idle Air Control Valve? New fuel filter? Just trying everything.

Brently

[Bluebimma]

Exhaust leak wont cause a misfire, you need to check for grounding issues, coil pack boot failure, premature grounding of coils in the cylinder wells, then step into the other areas of diagnosis. Also, a video would help actual mechanics help you with this issue.

[mzender]

Sounds like the issue I just had, mine was a somewhat common issue. Sometimes when changing plugs a piece of carbon may fall into the cylinder and when you start it, it becomes stuck in a valve seat causing it to not close and misfire. Just driving it 50 or so miles is the cure. I'd just pull the cover off quick and do a visual check to be sure everything's good, tight, and connected right.. If all is good, go for a cruise and put a few miles on and see if it clears itself up.

[LeeV]

I pulled off the boot goin gfrom the MAF to the throttle body and it was really damaged had tears in it, along with the nipples for the air lines cominginto it or out however you want to look at it and they were wrecked too. So ordering a new one, Thank you all for the help i will post again when i get the part for a update.

ok so i got my part it helped a little but i found the main problem....

I pulled each harness from each coil as the car was running only Cyl 3 did not effect the idle, i pulled the coil and replaced it with one i knew was working. Still the #3 was not firing, what can i do to solve this problem, what are common failures? Does the harness go out? How I got all types of multi meters Curcuit testers, just please tell me what i can do and i will try If you need more info PM me. thanks Lee

[LeeV]

ok well now i got power to the coil only 6 volts though. could this be a computer issue or something else? please help. thank you all for your help.

[la02max]

Definitely a vacuum leak...they make fogger kits that you can use to detect a leak. I just replaced my IM gaskets, and a couple of lines that I thought looked crappy, and it fixed mine right away.