I was driving home from Houston today and the cobalt electronic fuel pressure gauge pins all the way high. The truck ran fine, no CEL, the wideband didn't run rich, was at 11.5 in boost....bad gauge? I pulled over to turn the truck off and see if there was any problems. Truck idled fine everything else was normal...bad gauge or sending unit??

 

Mine does that once in a blue moon. When I turn the truck off for a while it reads correctly.

 

I would look towards the sending unit or maybe a wire that is grounding out. I doubt it is the gauge.

 

Mine was doing it for a few days way back when, hasn't done it since.

 

check your ground or the signal wire IMO. If the signal wire is broken, the gauge will peg.

 

went back to normal today...thanks guys

 

When i first installed my cobalt gauge it did the same thing, at first i thought it was a calibration issue but then it just went away.

Dustin

 

Make sure moisture is not getting in the connection at the sending unit. Like has already been said, when the signal is lost it will peg out. Mine stared doing that randomly then after a few times, it started reading ~20# low. I called Autometer and they said to replace the sending unit. Replaced it and has been fine since.

 

it is an issue with the gauge/sending unit. I've replaced both and mine does it every once in a while. seam to be more likely to happen turning long road trips... POS autometer.....