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bloodspatteranalyst
07-11-2014, 09:13 AM
I get this problem about 20% of the time. I'll turn the key, it'll crank just fine (no slow crank/battery issues) and then die out for a split second, and then start right up. It's almost like it's hesitating between dying out and starting up. If in the event it does die out, it starts up instantly on the second crank.

I don't think it's a starter issue (it was replaced in the last 2 years). I thought it could be the battery but I'm not experiencing slow crank. One of the fuel injectors was replaced recently. I'm thinking it could be the fuel filter, which has no record of being replaced.

I do smell fuel when I start the car but it's not particularly pungent. I kind of just catch a whiff when I reverse out of my parking spot. Treating my fuel system with the Chevron fuel system cleaner has helped somewhat, but not much.

Any ideas? I could try to record a soundclip if that helps.

Avetiso
07-11-2014, 09:37 AM
Fuel pump relay. It can soft fail and work intermittently

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az3579
07-11-2014, 09:44 AM
Vacuum leak. Do you have any other weird idle issues or performance issues?

ryankokesh
07-11-2014, 10:15 AM
Fuel pump relay. It can soft fail and work intermittently

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You can do a quick test by switching the horn relay with the fuel pump relay and see if it helps. Diagrams (http://www.bmwgm5.com/e46_relays.htm)

bloodspatteranalyst
07-11-2014, 01:56 PM
Didn't consider a vacuum leak. I don't get any hesitation/misfiring/codes, but when my car starts "with hesitation" as described above, it idles at 1000rpm for a min or two before dipping down to 600. If it starts normally (80% of the time), it idles at 600 from the get go.

I will read more on the fuel pump relay. Don't know much about it but it sounds like a good place to start.

ryankokesh
07-11-2014, 03:15 PM
If your fuel filter hasn't been replaced yet, I'd do that too whether it's causing your problem or not.


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danewilson77
07-11-2014, 04:46 PM
No SES light?

bloodspatteranalyst
07-11-2014, 05:01 PM
No lights. And yeah, I'm going to do the fuel filter soon.

Simmsled
10-30-2014, 04:28 PM
OP, did you ever figure this one out?
This sounds similar to an issue that I'm having.