Need help
#11
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My Ride: E60 545i stock
Model Year: 2004
Depending on how serious the problem is and how concerned you are about a small oil burning problem and local regulations, I wouldn't do anything until you see smoke all the time. That could be a while before it gets much worse, if its really only the stem seal problem.
#12
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I think the clue that's significant is that it seems to run fine after it's warmed up. The scenario that pops to mind is the difference between the open loop condition (from a cold start, until your upstream (pre-cat) O2 sensor is fully warmed up) and closed loop (when your engine management software is using readings from your O2 sensor to set the fuel injection parameters).
If there's a problem with the fuel pressure (for example) the pre-set "program" for start-up operation might result in too-lean or too-rich operation. Then, when your O2 sensor reaches proper operating temperature, the ECM could adjust accordingly.
But there are other things that can cause misfires in the cold-start scenario - check your air filter, vacuum leaks, etc.
If there's a problem with the fuel pressure (for example) the pre-set "program" for start-up operation might result in too-lean or too-rich operation. Then, when your O2 sensor reaches proper operating temperature, the ECM could adjust accordingly.
But there are other things that can cause misfires in the cold-start scenario - check your air filter, vacuum leaks, etc.
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