MAF Sensor limits
 

Got a CEL monday morning it was a P1126, checked the MAF, looked clean, cleaned out the air filter and found it was rather dirty. Put it all back together and I am getting hesitation between 3.5k an 4k. Went out and decided to test the MAF with some info I found online. Upon testing the MAF I find the following, at idle I am getting 2.5v from pin 1 and 1.5v on pin 5. I pulled the sensor out and it is very clean, should it be dirty to need cleaning, or should I clean it anyhow. Could it be a fuel filter or something worse. Its a 01 S so I am not sure if its an external filter or not.

I would clean it anyway and see if that clears up the problem. its only a few dollars. mine looked very clean too but still threw a code. the MAF itself could have gone bad all together. im not sure how frequent that is. fuel filter is pretty easy. but o2 sensors if its them start to cost a pretty penny like the MAF

Have you driven it long enough for it to relearn
 

and reset itself?

not sure if you are talking to the OP or me. but ill clarify my statement. it looked clean but was still throwing a code so i went ahead and cleaned it anyway and it fixed the issue. :cheers: