Rough Idle MAF Issue (1 Viewer)

[jahawk]

I've got a rough idle issue on my 2002, no codes. I hooked the scanner up and looked at the live data. My MAF is reading .01 to .02 depending on RPM. Should it not be in the 5.0 range? Anyone ever have a MAF go south with no does being thrown?

Thanks,
Jim

 

[gregnash]

Get a hold of the FSMs and it will tell you for sure.
Have you checked your battery connections to ensure everything is good?
How about spark plugs and coil packs? Know how old they are?
What makes you believe it is the MAF? Simply the numbers you reported?

 

[white_lx]

I've got a rough idle issue on my 2002, no codes. I hooked the scanner up and looked at the live data. My MAF is reading .01 to .02 depending on RPM. Should it not be in the 5.0 range? Anyone ever have a MAF go south with no does being thrown?

Verify your units. It could be set for pounds/sec. 5 g/s = 0.01 lb/s.

 

[87warrior]

Can you see what CFM reading the MAF is providing with your scan tool?

I've had a failing MAF that would cause a rough idle, stalling at low speeds and general poor drive-ability. When the MAF would 'fail' it would peg the CFM reading to 1,300cfm. Cleaning did not help, but a new MAF from Toyota fixed it. I never had the CEL trigger because of the MAF, unless it was because I forgot to plug it in after doing work.

 

[jahawk]

Verify your units. It could be set for pounds/sec. 5 g/s = 0.01 lb/s.

It is set to pounds.

I pulled the plugs and they look good. No idea on the coils. I checked for vacuum leaks, changed the PCV, fuel filter, etc.

I'm open to any ideas you may have.

 

[jahawk]

Can you see what CFM reading the MAF is providing with your scan tool?
View attachment 2209805

I've had a failing MAF that would cause a rough idle, stalling at low speeds and general poor drive-ability. When the MAF would 'fail' it would peg the CFM reading to 1,300cfm. Cleaning did not help, but a new MAF from Toyota fixed it. I never had the CEL trigger because of the MAF, unless it was because I forgot to plug it in after doing work.

I don't believe my scanner reads CFM but I'll check.

 

[abuck99]

Check the O-ring on the MAF and see if its flattened out or flush with MAF body ie. not sealing well. You may be getting some air leaking past it. And I’ll state the obvious- be sure to clean maf sensors with maf cleaner (not brake cleaner.)