[FIXED] 2008 Tundra CM 4x4 5.7L - Engine Code P0102

So yesterday i was driving home from the store, and as i was accelerating from a red light, all of a sudden the throttle cut out on me, felt almost like the brakes had been applied. after a second or two, it did let me continue to drive, although the idle was rough and the truck lacked power. there was a CEL on the dash as well with the VSC light on also. i had driven about 10 mins to the store, idled for another 10 mins or so at an ATM machine, and it was only after leaving the ATM and taking off from the red light that this occurred, so it had plenty of time to warm up.

When I scanned the code, it was P0102 - Mass or Volume Air Flow Circuit low Input

I've already checked to make sure there are no air leaks anywhere from the air box to the throttle body.
I've pulled the MAF out (carefully) and cleaned it really good with some CRC MAF cleaner (i did not physically touch any of the wires with anything other than the spray from the MAF cleaner)
I've cleaned the throttle body really good with some TB cleaner and a shop rag to get all the buildup off (there wasn't much).
There are no vacuum leaks on any of the hoses on the top of the engine.
There are no cut/frayed/corroded wires on the wiring harness that plugs into the MAF.

so ruling all of that out, these are the other options that i was able to find as possible causes:

faulty MAF sensor
faulty PCM
faulty MAP sensor
clogged catalytic converter
faulty air injection pump

Truck has 133k miles on it.

anyone know of a way to narrow down the issue a little more, preferably inexpensively?
I don't know of anyone with a 5.7L Toyota engine who is willing to let me try out their MAF or MAP sensors to see if that's the cause.

 

My check engine light came on when I "I've pulled the MAF out (carefully) and cleaned it really good with some CRC MAF cleaner (i did not physically touch any of the wires with anything other than the spray from the MAF cleaner)" I disconnected the negative on the battery. It came back on, but I just drove it for a couple days and the light went off.

I think it's because the MAF thinks there's a foreign object or substance on the MAF.

I'm not a mechanic in any way though.

 

Borrow a scan tool that has live data and let us know what the MAF is reporting at idle. If the scan tool can log data, try slowly revving up the engine and see what the MAF data does. It should also slowly increase.

How are your short term and long term fuel trims?

 

I have the Torque Pro app that connects thru bluetooth to an OBD-II module, readings at idle are in the attached screenshot.

STFT1 = Short Term Fuel Trim, Bank 1
LTFT1 = Long Term Fuel Trim, Bank 1
STFT2 = Short Term Fuel Trim, Bank 2
LTFT2 = Long Term Fuel Trim, Bank 2

The MAF reading does not change at all when I rev the engine. LTFT2 changes from -0.78 to just plain 0, all the other fuel trims stay the same.

 

If the MAF is giving you a reading but not changing when you rev up the motor, I would go ahead and swap it out for a new (OE) one.

 

good call, replaced the MAF sensor and all is well....thx for the assist