Thread: Outback out
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Old 03-02-2018, 05:16 PM   #6
John V
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Join Date: Apr 2005
Carmudgeonly Ride: Ram, MS3, CX-5, RX-8
Location: Glenwood, MD
Posts: 14,753
It will eventually register a misfire code if it's idling that badly. It should have stored codes in it (CEL came on) even though you disconnected the battery. I'm not understanding why it doesn't.

It sounds like a bad crank sensor to me. Bad cam sensors will usually cause hard starting but once the engine figures out where TDC is it should ignore the cam sensor for the most part.

Drive it around until it throws a code. It might take ten miles or so.

Odd similar story. When I was working on Matt's 330i, the first drive after I had done all the work on it went fairly badly. It had a bad misfire, and it wouldn't throw a code. I pulled all the plugs and they looked fine. I pulled all the coil packs and they looked fine and ohmed out okay. Eventually it threw a CEL for cylinder 4 misfiring but I had to drive it for 5-6 miles. It turned out that hole had a bad spark plug (brand new!), the ceramic insulator had a tiny hairline crack in it.
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