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Old 10-20-2023, 01:40 PM
racebmwm3 racebmwm3 is offline
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Quote:
Originally Posted by andrewwynn View Post
Smoke test but you can also use an unlit propane torch to spray near suspect areas while watching O₂ feedback real-time. BB is a giant diaphragm so can easily be a bug vacuum leak. You can pinch off the hose to test while watching O₂ or STFT.

Also; FPR uses vacuum hose for pressure reference to intake. You said that was replaced if that's plugged can cause fuel pressure problems.

Odd to see high fuel pressure and also high positive trims.

Can also be MAF sensor reporting wrong air value. The baseline calculation based on MAF the car adjusts fuel after the fact.

The error you're getting says there is unmetered air but it's the identical affect of MAF reporting inaccurate=low quantity.
I've tried spraying carb cleaner all over the place before and after the engine has heated up, but I have not observed a change in engine idle.

If it was the MAF, wouldn't it show lean right after start up? Mine is showing fine after start up, but pegs lean after 20 mins of warm up.
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