Here's one I've never seen...7 psi boost at idle!

[kevin87turbot]

Lol. I don't know what's happening with this one. I'm trying to do a remote tune, but it's doing some weird stuff. The MAP dances from 50 to 150 kPa at low rpms and goes up to 207 kPa at upper rpms. It's a turbo 4.8L with 4L80E. I've never seen one quite like this. The MAP appears to be correct with engine off...around 98kPa. It typically idles at 56-58kPa...but as soon at he gives it any throttle, it immediately jumps to 140-150kPa. It's very odd. Could it be a bad sensor or electrical noise or ? Any help would be greatly appreciated!
log 11.hpl

[SultanHassanMasTuning]

bad harness/map sensor i assume

[01SLPSSM6]

I have had that happen recently. It ended up being a bad map sensor. Key on engine off kpa was correct, idle kpa was correct, but as soon as you would start driving the map sensor would start spiking and read boost pressure when it was not. The reason the map went bad is the map sensor blew out of the intake and hit the firewall when it was under boost. New map fixed it. Definitely check the wiring connections too if it has a different connector spliced in.