The other day, we were hauling our 2000lb boat/trailer combo up thru the cascade mountains, and I noticed that the Tahoe seemed a little low on power. I've only had the Tahoe a month or two so far, and before that, had been completely reliable. Anyhow, I noticed the RPM gauge seemed to be almost sticking, and jumping around. It's almost as if it wasn't registering small engine RPM changes, but only biggers ones such as when you change gears, or drop/raise RPM's noticably. And it didn't move smoothly. It would just jump up or down in correlation to the RPM changes. Then, it bogged down just a little while driving up an incline, and then the check engine light came on. We immediately pulled over. All temperature gauges read fine. After that, we hopped back in, and started her up. CEL was off.

On the way home, we suffered the same issue of the jumping/sticking RPM gauge, but didn't experience a CEL. My brother in law said a lot of times it'll point to an emissions problem, but he's a Honda guy as well, and I know the CEL registers a lot more codes than just emissions.

I try to do mechanical work myself as I'm pretty handy with a wrench, but when it comes to diagnosing stuff, sometimes I can be a little clueless, but have no problems getting my hands dirty if I know what needs to be accomplished. I've been reading up on symptoms like this, and on a honda forum, someone mentioned that on their cars, the jumping RPM gauge/CEL can point to a distributer that's on it's way out. Does the same hold true for our Tahoes?

Any suggestions would be more than appreciated. Thanks!