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

 

That looks like I caught fire at some point. I'd be very concerned.

 

My guess is someone cleaned it with a solvent and either set it on fire or got too close to heat source?

Throw it in the bin and get a new one from Rock Auto, your CEL/RP should go off after a few drive cycles if not get them switched off.

 

I wouldn't run the vehicle at all with the deformation to the sensor tube. Just sayin'

 

My answer to your question is ----- a ----- no. Your fuel trims will be out of this world, as all the other sensors will be going crazy.

 

The car relies on the MAF. It's vital it works right. It's one of the very few that must be right (CKP tends to be another).

I can't say yours doesn't work right but it sure looks doubtful!

There again, if it's running CL (closed loop) - is it? - and not throwing codes then it's within limits. You could check the fuel trims.

I'd get a scrap sensor for a few $$$, clean it and fit it. Or OE if cheap.

 

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.

 

Should clear (*) after 3 warm ups.

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.

 

Go get yourself a new one buddy! That thing will throw incorrect readings as to how much air enters.