Mafs code low signal a

[Clark Volk]

Stays runnin regardless plugged in un plugged shifts terrible pigtail stest fine key on zero reading on scan tool please help have swapped sensor same thing

 

[Clark Volk]

Stays runnin regardless plugged in un plugged shifts terrible pigtail stest fine key on zero reading on scan tool please help have swapped sensor same thing

If i reset code with key on then research for cods wont pop up until i start engine but if reset while running it wont clear

 

[smdk2500]

Vehicle, year, engine?

 

[Clark Volk]

Vehicle, year, engine?

1999 gmc yukon denali 5.7l vortec l31

 

[Clark Volk]

An i mean nothin on scqn tool 0 engine load 0 maf frequency 0 maf voltage

 

[Clark Volk]

An i mean nothin on scqn tool 0 engine load 0 maf frequency 0 maf voltage also all started after melting pigtail on headers cut off behind melt rewired new pigtail not this is my issue

 

[Schurkey]

Either the truck has additional problems, or the scan tool does.

Connect scan tool to a similar truck, see if you get MAF readings. If you do, your truck needs wiring help, a non-defective computer, or a non-defective MAF sensor. If it doesn't, your scan tool needs to be upgraded.

What scan tool are you using? Have you ever gotten MAF readings with that tool on this vehicle? On other vehicles?

 

[Clark Volk]

Either the truck has additional problems, or the scan tool does.

Connect scan tool to a similar truck, see if you get MAF readings. If you do, your truck needs wiring help, a non-defective computer, or a non-defective MAF sensor. If it doesn't, your scan tool needs to be upgraded.

What scan tool are you using? Have you ever gotten MAF readings with that tool on this vehicle? On other vehicles?

Autel mk808 yes on this vehicle an others i doont wanna buy 180plus$ mafs this one isent barly 6 mos old

 

[Clark Volk]

So im as far back with wires as where th 3 go into bigger part of harness aginst fire wall should i just keep pulling loom an tape follow an inspect

 

[Schurkey]

You've gotten MAF readings on this truck prior to the wires melting on the exhaust?

I'd double-check the splices. And if they're good, I wonder if the computer guts shorted-out somehow when the harness melted.

Any popped fuses?