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Help! Recently realized my mass airflow sensor on my K&N air intake was missing bottom 10 mm bold on the housing which holds the sensor. I tightened it back up and Now I have light and engine codes all referencing mass air flow sensor. I disconnected battery to reset, installed new sensor, started it up and no engine light. Drove it for 25 minutes no engine light. Next morning start it and engine light!
Can’t understand that when it was loose, no light, but when tightened with new sensor light!
Trying to understand what you’re doing here ??…was the MAF changed and then you noticed the bolt missing and then you have the MIL back on…or you noticed a missing bolt and now you replaced the MAF sensor and now the MIL is on ??…just trying to see what was done in some kind of order !!
What was the code ??…there is wiring to the MAF so it’s not always the MAF and you never change a part based on a code unless you diagnose it…is the new MAF OEM or an aftermarket !!…there are a lot of bad new parts out there these days !!
I’m assuming you have a scan tool so the first thing I check is BARO or MAP in inHg with engine off….a skewed MAP sensor can cause a P0101…with the engine fully warmed up your MAF in grams/second should roughly be the liter displacement of the engine…a dirty throttle body can also cause a P0101…if your scan tool shows TPS % it should be less than 10%…(see picture)…
if you have a voltmeter remove the MAF connector….with ignition on you should have 5 volts on the yellow wire, 12 or system voltage on the pink and less than 100mv on ground…with engine running if you have a voltmeter you should see around 4.3 volts at idle…and make sure you have no vacuum leaks !!…what are your long and short term fuel trims at idle ??
I'm going to take the air filter to the throttle body off and check/clean everything. What I find perplexing is when the housing that holds the MAF sensor was incredibly loose, no doubt sucking air in, the engine light Never came on, yet when secured and then replaced, it came on. ???
I appreciate all your advice, I don't have some of the gear needed but I will take pictures of your pics and run it by my mechanic. I'll keep you informed. Any advice if I have to take on not getting fucked if I have to take it to a dealer?
Semper Fi Veteran!
Al
No need to take it to a dealership…where are you located ??…I’d find a diagnostic shop in your area and not a repair shop…most have poor diagnostic skills…they can change brakes to beat the band but diagnostics is a whole different skill set…they will just shotgun parts unfortunately!!
Did you ever did a solution? I noticed the boot was loose on my throttle body so I tightened the clamp. Then I ended up getting a mass air code along with rich and lean. So I cleaned the mass airflow sensor with airflow sensor cleaner decode went away came back, so I am replaced the mass airflow sensor with a new one the light went away, but quickly came back after a few short miles
Did you ever did a solution? I noticed the boot was loose on my throttle body so I tightened the clamp. Then I ended up getting a mass air code along with rich and lean. So I cleaned the mass airflow sensor with airflow sensor cleaner decode went away came back, so I am replaced the mass airflow sensor with a new one the light went away, but quickly came back after a few short miles
Did you install a junk aftermarket sensor ??…that would be my first thought. You also have to check the MAF wiring because if the wiring is faulty the sensor will not work correctly.
Mass Airflow Sensor
