The smoke test is a good suggestion and I will look into getting that done next.



I am seeing realistic airflow values from the MAF (using my Foxwell real-time data). That doesn't mean that the MAF is truly reporting correct values, but the signal looks like the right shape and I believe the idle reading was about 3.5 g/s which is reasonable. I have read about others replacing the MAF when it gets this old, but it doesn't seem to fix everybody's problems.



I see the fuel pressure suggestion a lot, but in my searches I have never read about any BMW owner who actually found a fuel pressure problem causing a problem like this, or fixed this problem by replacing the pump. It seems like it would be a very odd way for the fuel pump or pressure control valve to fail. However, I fully expect and intend to eat my words if and when I am proven wrong.

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2003 3.0 5MT Topasblau
Purchased in 2016 and sold in 2024
2012 35d Platingrau