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My CEL is on plus occasional "performance reduced" or whatever it says with yellow warning light. This pretty much out of nowhere. Code is 0171 which is lean RH bank but car feels completely normal.
I did find out that a local brake and oil change joint left the air box partially open to outside non-filtered air last time car was in there a month or so ago. I put it right but pulled out air mass sensor to see if it got dirty. This is what is looks like. Can it be left in until it totally fails or is this a failure state on its face? Thank you. --Tom
Updating myself here; got delphi unit from local autozone for $80USD. It looks a little different in air scoop shape but the little wire on the side is the same. Physical fit and plug are identical to original. The car runs pretty normally which it was doing before but the CEL has not gone out yet. Hoping it will eventually clear.
But do check the fuel trims anyway. You can catch a problem early that's not yet throwing codes but is doing damage plus it's always nice to fix things before they get bad.
(*) the MIL; the code will remain stored for at least 40 but is simply there for diagnostic reasons
Thank you but how does owner check fuel trim without special gear? I kind of want a mongoose but am afraid I will screw something up or fail to get it to work properly. If there is a home brew DIY way to check (or adjust?) fuel trim, I would like to know what that is. --Tom in AZ
Hi you cant adjust fuel trims just monitor: except with mapping software.
It can be done using an Iphone or android phone/tablet app and a bluetooth obd2 reader reader costs about 12quid.
I use Torque Pro on android for simple checks it costs 4 quid so relatively inexpensive, with a great range of live data checks.