Is there anything other than a bad TPS that would cause RPM surge while cruising? My Jeep just started doing this again within the last 10-12 days, and it's somewhat sporadic at the moment. It seems to only do it after I've been driving for awhile. My Jeep doesn't currently exhibit erratic idle, which is another symptom of a bad TPS, but the RPM surge is pretty much identical to what it was doing when my original TPS went bad. When the original TPS failed, I also had an erratic idle. I took it to a dealer today, and their diagnostics found nothing wrong. Can a TPS fail gradually? I would assume that it could due to the mechanical/electrical nature of the part.