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Assistance with troubleshooting MAF

1781 Views 41 Replies 6 Participants Last post by  PeterDuerr
Hey guys,

I have an issue with my mass airflow sensor. I have just received my tunercat cable and I'm reading data via $eehack (thanks for the tip @Marky Dissod)

I have also received my PCM back from a mail in tune.

My mass air flow reads 0.00g/s. I do have 12v and ground at the connector. I couldn't check the signal wire. (Its plugged in).

I have trouble codes/ CEL : "MALF 43c active" and ERR43(esc failure). I'm assuming this is the same as DTC 43 (knock sensor)?

Why am I reading nothing on the MAF but not getting DTC 48? Is this part of the tune?
The knock retard is at 0 deg. And a think im not receiving knocks.

Also oil temp is all red failled low.

Is this as simple as needing a new MAF sensor?
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My current speculation is that with the call for both fans to run because of the MIL code, it creats a high current draw which somehow cuts out the dash.
What MIL code do you think would trigger both radiator fans?

My digital dash also started to cut out on top of it all which added to the confusion.
There were issues with the digital dash from the factory. In the majority of cases the final solution is to fix the solder cracks on the circuit board.

No special request. He's the profesional so I'm trusting he knows his stuff. The way he has it tuned, the MAF is red and reading zero on eehack. There may be some things going on in the back end.
DTC43 knock sensor is the code.
As per FSM DTC 43 PCM will default to retarding timing based on current RPM and MAP. Loss of performance.

Does Eehack show a valid temperature for the coolant?
A/C can trigger both fans as well.
8a-20-10 did have the connector, thanks!

I'll also confirm the temp this weekend. I seem to remember it being acurate.

I didn't see and retarded time on eehack. I updated the initial pictures to full size. You may be able to see those values now.ÿ
Ask your tuner if he is ok with you downloading and saving his tune ( like he has a choice) and plugging in a stock calibration to see what happens.
Many of us here could send you a stock 95 Impala cal .
Mine would be a tunercat .bin or Lt1edit .lt1
Thats good to know, Thanks!
I may hit you up for that in the future. Can flashhack load a tunercat.bin? Are all .bin's the same?
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Can flashHack load a tunercat.bin?
Are all .bin's the same?
No such thing as a TunerCAT .bin. A .bin file is a .bin file.

Peter, the tuned .bin file in your pcm is yours. You paid for it.
You can definitely read it out for yourself.
If you can read it from the pcm, maybe call it
pcmp_speednst.bin ?

Do you have TunerCAT or TunerPro yet?
Ok, that makes sence. I have eehack and flashhack dowloaded. I havn't used flashhack yet.
FlashHack is for reading .bin files from & writing .bin files to pcms.
$EEhack is for diagnostics, and trying temporary experimental changes.
TunerPro is for editing .bin files (before loading them into a pcm with FlashHack).
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The off brand knock sensors I installed are reading a bad resistance. Hence the knock sensor code. Should have at checked resistance before installing. ACdelco on the way. Lesson learned.
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Knock sensors are easily faked. Only buy name brand from a reputable supply chain. I wish I could find the cutaway images I saw one time on the internet of some that literally just had a resistor inside. No piezo at all.
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Well.... after I remove these. I will refrain from hucking them down the driveway, driving over them and setting them on fire. I'll atempt to open them up instead.
Ok so it appears to have a piezio. I think thats the white plate that gave me a static shock when I touched it.
It actually has a 100kohm resister installed.
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For the record it is an Ultra Power sensor.
Looks like you were able to drain out the block though ... ?
Yup, twice now. Hahah. Thanks Ultra Power! A quick google seach shows the 100kohm for a different chevy block, so maybe I should blame rock auto not ultra power. @Z09B4U . This builds his case most definatly.
Parts manufacturers that have been reliable in the past are producing duds and leaving it to the end user to "sort it out". This is where a good relationship with a local parts place pays off. They may not be the cheapest but some still take care of their customers. It was the locals that bailed me out the last time RO sent me two different rear calipers.
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Come on, man. Blame rockauto for your selecting the cheapest part they offered.
The Delphi part would have been a far better choice in my opinion. Or, AC Delco from a dealer, etc.
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