AJ123

Thanks for the correction.

puzzigully

OK,

next installment:

inserted probes into terminal C and D of the MAF.

Attached two Voltmeters to check:
1. if 12V is indeed being sent to the MAF
2. What is the voltage getting sent to the ECM.
I took videos immediately after engine shut down

I'm confident that #1 is working as I can see the MAF burn off.

Here is the video of #1.
So all shows good. As expected

Next is Terminal C video.
Was lucky to get the MAF and meter in the one shot, so you can see it happening:

looks funky....expect I'm needing a new MAF?

comments?

AJ123

That is exactly what John found on mine. Just order one dont give them the core until after you test. Voltage should have dropped when the burn took place c is the green wire which sends the info back to the ECM.

puzzigully

Thanks!

So have you no longer got a code 36?

Did you go with the Cardone MAF, or another brand?

AJ123

yes Cardone an no codes yet
Knock on wood

puzzigully

I'll pre-order the MAF from O'Rriellys as I'm heading over on Sunday, so will pick that up and bring it back to Oz (fingers crossed it fixes it)

I'm curious to know why the MAf isnt sending a signal back to the ECM.
I wonder if it's an internal failure within the MAF itself.
Be good if there's an easy check you could do to determine if the MAF is faulty in this manner...

There must be a problem/disconnect within the circuit that once the burn off is happening, it doesn't send out the info for some reason.

Anyone seen an internal circuit diagram for a 1987 Corvette MAF?
Or even a MAF with a burn off circuit??

AJ123

Good luck

AJ123

Well still no code 36
Adjusted tb fixed a few cracked vacuum lines running great

puzzigully

Awesome!!

Cliff Harris

This diagram is for a 1985, but I don't think any of the internal MAF connections changed in 1986 - 1988:

puzzigully

Thanks John,

I was looking for some more detail that that diagram....more about the circuit of how the output is wired internally to take info from two sources (technically the same source, but different inputs to that source) and send to the ECM

Cliff Harris

I have an extra MAF and I plan on taking it apart and tracing the internal circuit some time in the relatively near future.

AJ123

Very interested to find out the answer also

puzzigully

When I get my new one and it proves to be ok, I'll do the same.

It's such a common failure, there has to be a reason for it.

AJ123

Well I know I got lucky with my friend John figuring it out took him almost a full month.

AJ123

Driven corvette every day No codes

looks like I got lucky problem solved


puzzigully

hope your problem is solved

puzzigully

Me too!

I'm in California right now, return on Monday, can't wait to fit the replacement I purchased from O'Riellys and see if it solves the problem...

Actually went to a auto salvage yard today to try to find one on a wreck, wasnt any thing there.....

Fingers crossed the new one works

AJ123

good luck

puzzigully

Returned home with the new MAF sensor in my hand luggage.

Just came in from the shed after fitting it up, fingers crossed...

STILL HAVE CODE 36!!!!!

No clue what to do now

AJ123

This is such a pain
I feel for you
Mine is still running great
I guess I just got lucky