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MAF not reading

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Old 10-15-2018, 11:09 AM
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Default MAF not reading

After a Trans swap back to a 4L60E, my MAF is not reading and throwing P0121.

Voltage at MAF with key on, not hooked to MAF
Yellow 4.97v
Pink .48v

Hooked up to MAF
Yellow 2.21v
Pink .21v
White and black 1.48v
Tan .03v

Removed and reinstalled Volant intake tube to make sure the lip wasn't caught at the bottom side of the throttle body.
Used a can of brake parts cleaner to hose around the intake manifold and sensor holes to see if it bogged, it didn't.
I read on another thread that setting the tune back to stock helped bring it back? No idea.

Mods are
Volant intake
Dynatech long tubes and catted Y pipe
ported and cut 862s
208/212 Comp Cam

Anything I'm missing? Checked the grounds, this is a new issue since I put the cam in 12,000 miles ago.
Old 10-16-2018, 10:38 AM
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Pink s/b +12v referenced to gnd with key on. But if you are referencing to the gnd wire on the MAF the gnd could be open. What you are missing in the post is any mention of what the vehicle is.
Old 10-16-2018, 11:56 AM
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2008 Avalanche 5.3
Old 10-16-2018, 12:57 PM
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Checked voltage from MAF and grounded to battery. Same .41v at the pink wire. 2.4 at yellow wire grounded to battery.
Old 10-17-2018, 12:17 AM
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Check Eng fuse 4. 15A
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Drspencer (08-29-2019)
Old 10-17-2018, 09:15 AM
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Guy thinks he’s pretty smart. If my attachments would upload, I’d upload the 15A fuse that was blown at 4...
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