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Old 10-08-2012, 01:42 PM
Supercourse Supercourse is offline
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Location: British Columbia, Canada
Join Date: Feb 2008
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Mein Auto: 2004 X3 2.5i
Originally Posted by thompsonmd View Post
.... Upon starting the engine runs rough for a few seconds, then it is fine.

...... It only does this if it has been sitting for a few hours.

.... codes for both banks, P0171 and P0174.

.... filthy air filter,

.... He suggested that perhaps a fuel injector slowly leaks when the car is off, building up fuel in the cylinder.
The indy guy's suggestion sounds very plausible except it doesn't explain the lean codes.

A cracked intake boot, or problems with DISA, fuel filter, or fuel pump should present symptoms other than just at first start up.

Was the air filter element very dirty because there was an oil film on it?
Did much dirt come off the MAF when sprayed?
Did the original plugs look as expected after 85K miles?

Could be early waring signs of a clogged crankcase vent valve/oil separator:
- bit of oil on plugs needs to get burned off after a cold start but not enough to affect warm start
- P0171 and P0174 codes consistent with CVV/CCV issues

Even though your oil consumption is not noticeable, might be worth ruling this out by the usual simple tests.
Such as checking underside of oil filler cap for goop, and checking for vacuum when cap is removed with engine running.
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