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Old 10-12-2010, 04:44 AM   #1
skuurt skuurt
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Default misfiring at low rpm acceleration

From idle to roughly 2,000 rpm I get misfiring when i give it gas. It goes away after 2,000 rpm and runs fine. I replaced the fuel pump, sea foamed it, ran injector cleaner, new spark plugs. My buddy said its the fuel filter which hasn't been changed since the car was new it looks like. I'm not that knowledgeable when it comes to cars other than the basics but I don't see how it could be causing this problem.

Also at idle my car searches for a steady RPM to sit at. it can bounce anywhere from 2-400 RPM. Any idea whats causing this problem also? could it relate to the first problem? although the idle has been like that since I bought the car a few months ago. the misfiring while driving is new.
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Old 10-13-2010, 09:22 PM   #2
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Check the coilpacks and the crank position sensor.
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Old 10-16-2010, 08:35 PM   #3
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Quote:
Originally Posted by trackjunkie21 View Post
Check the coilpacks and the crank position sensor.
Thanks. I actually went with the Mass airflow sensor and the throttle position sensor. checked the gapping of the spark plugs and everything went away.
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Old 01-12-2018, 01:09 PM   #4
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Just replaced the throttle position sensor in my '89 325i and it fixed the rough idle. Pelican parts has a good article on this. Also worth checking the idle control valve while you have it all apart.

Was your fuse #9 blowing also? For some reason mine was. I think the sensor replacement fixed it.
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