GXP Running Srange at Higher Speeds

[paulhunde]

Hey all,

My '05 GXP has been having some issues at higher speeds, like 65-70. The RPMs seem to fluctuate between 1800-2000, almost like it's shifting from gear to gear. Also does it with the cruise set. Could this just be a sensor, or maybe something with the active fuel management?

[Fivefingerdeathpunch]

AFM/DoD shouldn't make it vary RPM that much, it's not suppose to change the RPM at all when it's working anyway. It's only dropping to 4 cylinders and nothing else.

It could be TCC related, it's something you could watch on a scan tool to see what's really going on.