How do I test MAF?

[Lockleaf]

I am wondering how to test the MAF. I think I may have a malfunction there but I am not sure how to take the reading on it to get the info I need. I know what voltage readings I am supposed to be seeing, I just need to know what to connect with my multi meter in order to see what the MAF is telling me. Any help?

 

[StealthWyvern]

Just find someone local with another protege (same engine) and see if they will let you swap for testing.

 

[Pauljp]

Unless you have a tach meter it's going to be hard to do.
Some multi-meters have a frequency selector on it.
The MAF connector has 3 terminals, A-B-C.
A= Ground
B= Frequency pulse going to the PCM.
C= 12 vdc when key is on.
You will have to remove it. plug 12 volts to pin C and ground pin A.
Connect your tach meter to pin B and blow into the MAF.
Your frequency should increase as air flows through.
The reading should stay steady when no air movement is there.
Also, tap on the circuit board with no air movement and the reading should stay steady, if not, indicates a loose connections inside.
Good luck.

 

[Topdis]

Just a FYI. If you are getting errors pointing to the MAF, check to see if your air intake hose has cracks in it. They get stiff and brittle with age and develop cracks. When you start sucking air in after the MAF, the computer cannot properly compensate as it acts like the MAF is malfunctioning. Take the hose out completely and flex it slightly to look for cracks.

 

[P-Funk!]

^x2.

They really don't fail often on our cars - what is the 'issue'?

 

[MaxPower]

^x3.

 

[pureform]

yeah def look at the intake hose, it most likely will have a crack in the "accordion" section underneath possibly...I started having a rough idle in my '03 P5 last week and got a check engine light...everything I read online pointed towards a dirty EGR valve, but when I got the CEL code checked at auto zone it threw this: P0171..Which is a lean air/fuel ratio due to large vacuum leak or dirty MAF sensor...I took apart my intake to check for cracks and clean the MAF and immediately saw the crack underneath the Intake Hose..I taped it up for the time being and have been looking around online for a replacement part to no avail til I came across this blog post

here is a link to order the Dorman aftermarket replacement Intake Hose from https://www.amazon.com (commissions earned) if that is in fact the culprit.