Rough idle

Sabean · 05-07-2024, 08:32 AM

Need help only does this after setting overnight and running lean on bank 1
Recently done tune up new mass air flow
Can’t find any vacuum leaks either
The rpm vary from 1500 to 600

Hellshalfacre · 05-07-2024, 04:00 PM

Hello. It appears that you have a good sized vacuum leak. How are you looking for vacuum leaks? Even the cheap Amazon smoke testers work just fine for this. Highly recommend the smoke machine for pinpointing these kinds of leaks.
Other things that I've seen cause excessive ST/LT fuel trims are cheap aftermarket Valve covers, shoddily installed aftermarket intakes, and of course any hose connected to the intake. Good luck to you.

05-07-2024, 08:32 AM	#1
Sabean Registered 0 Rep 3 Posts Drives: 2013 x3 28i Join Date: Jan 2024 Location: STL iTrader: (0)	Need help only does this after setting overnight and running lean on bank 1 Recently done tune up new mass air flow Can’t find any vacuum leaks either The rpm vary from 1500 to 600 Attached Images
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05-07-2024, 04:00 PM	#2
Hellshalfacre Nothin to see here 51 Rep 43 Posts Drives: 2017 X3 sdrive28i, 2011 E88 Join Date: Apr 2023 Location: Florida iTrader: (0)	Hello. It appears that you have a good sized vacuum leak. How are you looking for vacuum leaks? Even the cheap Amazon smoke testers work just fine for this. Highly recommend the smoke machine for pinpointing these kinds of leaks. Other things that I've seen cause excessive ST/LT fuel trims are cheap aftermarket Valve covers, shoddily installed aftermarket intakes, and of course any hose connected to the intake. Good luck to you.
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