I have a 2003 Tahoe that I love but is driving me crazy with a "Reduced Engine Power" message. I am driving along and suddenly it dings at me, the message center says "reduced engine power" and I am losing speed. It goes into a "limp mode" in which I cannot accelerate, it cannot pull itself up a hill, and the engine misses badly. I can pull over, shut it off for a couple of minutes and then start it up and run again just fine until it decides to do it again.
There seems to be no rhyme or reason, one day it did it 4 times w/n the first 20 miles, then ran 100 miles w/o doing it at all. I recently took it on a trip that normally takes me 1 1/2 hours, it took 2 1/4 hrs that day because I had to pull over so many times. I was having to stop every 3-4 miles by the time I got there.
My usual mechanic has completely given up, told me to trade it. I have had it to another mechanic for over a month now, 3 times he has thought it was fixed, but it wasn't. One time, I didn't even make it the 5 miles to my house before it acted up again.
One other note on this: this past trip I made, I left early in the morning and my lights were flickering high/low. . . this went on for several miles. Finally my lights quit flickering, then I lost engine power, pulled over, shut it off. When I started it back up, the lights started flickering again. The cycle seemed to continue, once the lights would settle, the engine would lose power. I took it to a parts store and had the battery and alternator checked. They said both were fine. (Had never noticed the light thing before, but I can't think of a recent trip after dark.)
Anyone have any ideas that I can pass along to my mechanic?