Is this a diesel?
1. Valve stem seals. Fiddly to replace, but not difficult. Take your time.
2. The PCV diaphragm, though you mentioned you'd replaced it in the past.
3. Check your oil pressure, seals and gaskets around oil filter housing and such things.
4. Do a compression test to make sure your valves are sealing properly at TDC, not sure how applicable this is on a diesel. Depending on the result from this you may have bigger work ahead of you, such as valve cleaning, busted head gasket or something like worn piston rings.
Since you're mentioning that this only happens when the engine is warm and that it stops when you turn it off and on again, suggests to me it's a rich condition from the ECU. Perhaps ISTA is right and that this isn't a shadow code. The EGR valve is one thing, but there's a sensor also. Check and see that it's operable. You should be able to run a multimeter in resistance mode to see whether it's likely electrically fine. If the sensor doesn't think your EGR valve is operable, that probably causes the motor to run rich and if you then don't have proper sealing there might be smoke.
(08-14-2023, 12:42 PM)aade Wrote: Is this a diesel?Smoking can be a number of factors, but if you're burning oil I would try to take care of that or it might clog your cats. That's very expensive to fix. A few things to check (if it's a gasoline motor):
1. Valve stem seals. Fiddly to replace, but not difficult. Take your time.
2. The PCV diaphragm, though you mentioned you'd replaced it in the past.
3. Check your oil pressure, seals and gaskets around oil filter housing and such things.
4. Do a compression test to make sure your valves are sealing properly at TDC, not sure how applicable this is on a diesel. Depending on the result from this you may have bigger work ahead of you, such as valve cleaning, busted head gasket or something like worn piston rings.
Since you're mentioning that this only happens when the engine is warm and that it stops when you turn it off and on again, suggests to me it's a rich condition from the ECU. Perhaps ISTA is right and that this isn't a shadow code. The EGR valve is one thing, but there's a sensor also. Check and see that it's operable. You should be able to run a multimeter in resistance mode to see whether it's likely electrically fine. If the sensor doesn't think your EGR valve is operable, that probably causes the motor to run rich and if you then don't have proper sealing there might be smoke.
![[-]](https://www.bimmerscene.com/images/collapse.png)