P0102 MAF circuit low issue

[Tobyj17]

Trying to write a base tune for my new build. New at this tuning thing, but a mechanic by trade. Engine is an L92 6.0 out of a 2014 Chevy express van. Converted the harness to standalone, removed VVT, replaced the cam with an Elgin E-1840p, changed the valve springs, and have a 102mm throttle body and intake from Sharpe customs. I have been able to get the car to idle, but I am having a few issues. The first is that the MAF continues to fail. The MAF i am using is out of a 2014 Camaro, installed into some universal piping due to the stock express van MAF being integrated into the air filter housing. I recognized that the camaro has a different pinout, and I corrected that. I verified that my pinouts are correct, and I have checked the wiring from the MAF to the PCM. All is good. I have my 12 ignition volts and my 5v references. I've tried a second MAF (delphi) and I stilll get the P0102, and the MAF is not reading incoming airflow. I suspect it's something to do with the Hz reading from the stock express van to the Camaro, but i'm not 100%. Anyone have insight on this? Thanks

[danmw2003]

Circuit low faults are generally caused by a pinched wire, or a bad connection of some sort, causing high resistance in that circuit (loose connection). You need to find root cause of the excessive resistance in that circuit. Chances are, since you were pinning things out, you shove a paper clip in one of the pins to test it, and spread it. So that pin no longer has good contact with the male pin its mating to. Seen this more than a few times.

[Tobyj17]

No, i haven't done that. I know better. I checked pin tension and it is good. I do not have high resistance from the MAF to the pcm plug. Resistance is less than 1 ohm.

[danmw2003]

Uh ok? Well that's why it throws a circuit low fault. Resistance in the 5v , signal or signal return circuit is too high. But to each their own. Good luck figuring that one out.

[blindsquirrel]

No tune file to look at? No logs? It's hard to rule things in or out based on a story about some stuff that happened.

[Tobyj17]

I am using EFI live, that is why I did not post a log or tune file. I can post one if it helps and if you are able to read it. I'm new at the tuning thing, and new at asking for help.

I'm aware that high resistance or low voltages cause circuit faults. I have checked and verified the wiring and the voltages. I have 12v on pin C, ground on pin B, Pin A has less than 1ohm of resistance. The terminals are not spread. Intake air temp is reading correctly, so I did not check those wires.

[Tobyj17]

I understand. It won't let me attach files, it says that they are invalid. Can I send them to you?

[danmw2003]

If the circuits are good, then it could be a faulty ECM. I dont see how a tune would cause a circuit low fault, but stranger things can happen I guess. Considering this is the HP Tuner forums, you would need to post a HP tuner log file and calibration file for anyone to look at it. Unless of course someone has EFI Live available to them. That I cannot tell you. I know I only have and MPVI2 device.

[Tobyj17]

I wasn't sure if it was in the tune or not, as I went from the express van type MAF that was integrated into the filter housing to a card style out of the Camaro. I saw that I had the ability to change the hertz vs. grams/second and was wondering if maybe they had different voltage (or hertz) readings. I do have a spare ECM, I can certainly try it. I appreciate the help.

[2xLS1]

Are you checking MAF 12V using an arbitrary ground as a reference or the ground wire on the MAF. If the former, try referencing to the MAF ground wire. Could be an open ground on that wire and still read 12V using another ground.

[Tobyj17]

12v whether I use an engine ground or the MAF ground. There is also less than 1 ohm of resistance from the chassis ground to the MAF ground.

[blindsquirrel]

Thing is, there are settings in the tune file that'll fail the MAF and make it set a P0102. But asking about it here is kind of like taking your Buick to the Dodge dealership...

If you get no response to your post over on the other guys' forum, maybe it's because you didn't post any files to look at there either.

[Tobyj17]

I understand, i figured i'd get dragged being an EFI live user on an HP tuners forum. A lot of the terminology and stuff is pretty similar. I wish I would have gone with HP tuners, but I had several uses for my diesel stuff as well, and wanted something that was good at both. EFI live also had a few things I needed that HP wasn't capable of doing. I did not post logs or cals on the other forum, i just fixed that.

[GHuggins]

Well, the most common thing I see is the MAF installed backwards - opening should be to incoming air - not vice versa. This will still cause codes due to lack of airflow change on startup. Otherwise we need schematic and connector pics. You can try scaling the axis, but this theoretically shouldn't cause problems as long as the maf is reading air at the corresponding hz points.

[Tobyj17]

The Maf is installed correctly. Would tube diameter be an issue? I'm using a 4" pipe. I will check the wiring again. I ordered a new plug just for the hell of it too.

[blindsquirrel]

Oscilloscope/signal generator would have this sorted right quick.

[Tobyj17]

Update: the ECM was bad. I monitored the signal with an o-scope and i had signal. It was wired properly. With nothing else to try I used a different ECM i had, and the MAF started reading. So now I get to start over, hopefully to get a base tune written for this. Thanks to those that helped.