Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
The maf issue first showed up after a 700 mile trip. at time did not have funds to replace but was able to clear the code with OBDII reader and didn't come back for awhile. I changed the PCV valve and MAP sensor (only because i broke the MAP taking out PCV valve) and the MAF P0102 code came back. Took to youtube for help found scanner danner channel very helpful but still stumped. I did have a small lower intake leak which has been fixed. Now i can drive the car for awhile and no code but eventually it will come back. I have tested the plug and have 5 volt signal and power and ground and ohm tested sensor and it showed continuity. I have not been able to find any other vacuum leaks so i am not sure where to go. I do not have anything other than a DVOM at this time to test it. Thanks in advance for any thoughts.
Please clarify something for me. Do you have a 3 wire sensor with a yellow, pink (or pink blue) and black white ? You should have Bat + at the pink, ground at black white and with engine running some voltage at the yellow wire ?
Just to make sure, is the air filter okay and the sensor clean ?
Do you see different voltages at the yellow wire while at idle, 1500 and 2500 rpm ?
Thank you.
This sure sounds like an intermittent sensor issue to me. Given how infrequently the code sets, I think you'll have a very difficult time actually catching it in the act. Do you have access to scan data? A quick look at fuel trims at idle and under load would answer a lot of questions regarding the intake and fuel systems.
If the trims are reasonable, and you've done a careful inspection of the harness, then I'd probably go ahead with MAF replacement. I've had trouble with reman sensors in the past, so go new if at all possible.
I have a 3 wire pink, yellow, black/white. I have 12v on pink a little under 5 on yellow when running and a good ground. I have cleaned the maf with maf cleaner twice. I will look at air filter and have not performed the voltage test at different rpm but will.
Thank you! I don't have scan data available but since i have 3 boys who will have their own vehicles i am looking at a scope that would do the job and i think there is one on this site that would probably work.
Thank you. The variation on voltage that you have at different speeds just tells me that a signal is been generated by the sensor. In your case I believe that signal is a digital pulse to the ecm, so using your voltmeter set to Hz you should capture that frequency. So you have to start with the car at Idle as a baseline, voltmeter in Hz connected to battery ground and back probe the signal wire, take a measurement, then open the throttle and that measurement should change (increase) then when you release it should come back to that measurement you took at idle. Do it a few times and observe the results. If nothing changes, your MAF can has voltage output but the electronics inside can not produce a digital signal anymore; please post your results. Thank you.
