Hey all, new here. Just recently bought a 2008 suburban, 5.3 flex fuel, with the AFM issues. I replaced one collapsed lifter, followed a tutorial on how to cheaply "deactivate" AFM, then bought the OBDII "off switch".

Anyway, that all seems to be working just fine. Now the check engine light is on, when scanned there are 13 codes active.

P0106 - Manifold absolute pressure/barometric pressure sensor circuit range/performance
P0122 - Throttle/pedal position sensor/switch A circuit low
P0171 - System too lean bank 1
P0223 - Throttle/pedal position sensor/switch B circuit high
P0306 - Cylinder 6 misfire detected
P0352 - Ignition coil B primary control circuit/open
P0354 - Ignition coil D primary control circuit/open
P0355 - Ignition coil E primary control circuit/open
P0356 - Ignition coil F primary control circuit/open
P0357 - Ignition coil G primary control circuit/open
P1174 - Fuel trim cylinder balance malfunction bank 1
P1175 - Fuel trim cylinder balance malfunction bank 2
P3400 - Cylinder deactivation system bank 1

All electrical issues its lookin like, i'm not the best at tracking down and tracing these problems but I can if need be. Figured I would come here for help before I dove in.

Anybody had a similar a issue? Ground problem throwing all these codes? Any help would be greatly appreciated!

Thanks, Chase

 

Chances are you are correct suspecting a ground connection problem, the job now is to find it.

Because so many circuits appear to be involved, there is a good chance you might fine it much more easily starting right at the battery negative terminal and checking for a corroded or not connected ground wire between the ground connection where the negative cable is connected to the engine and the connection from that spot to other locations under the hood.. This should be easy to find because it supplies the ground path for so many components.

 

I'm suspicious of online cheaply deactivating AFM tutorials. May be the root of those issues / codes.