I just bought a 98 silverado with only 76,000 miles. The truck had never towed anything before. It has a tow package but had never been used. It is a 350 engine. The first time I towed with it (horses) the check engine light came on after 5 mins. The chevy dealer said it needed a tuneup since the plugs and wires looked like original equipment. The code for the light was 304 (misfire code). The next time I towed with it, the same thing, after 5 mins the light came on and same code (304). The dealer said it is most like from carbon buildup in the intake valves. So they cleaned them and flushed it with something and said that should do the trick. Does this sound reasonable and any suggestions? Thanks, Mike

 

you bought yours at 76k. sweet. i got mine at 68k too. anyhoo. to me that does sound realistic. i have a nitro r/c truck and if i just let it poke around idle a lot and not really let ir rip around it basicly lets the carbon deposits sit in the chamber and when i hit that throttle after a re-fuel it bogs a little then if you slowly build the engine stress it finally just opens and blows all of that carbon out and that principle goes for fullsize engines too. if that thing never towed and has 76k those are easy, slowly driven miles. the motor just hasnt seen weight before and is getting used to it. just like when you tow for a while then take the load off your motor is more alert and shifts different and reacts different due to the computer learning.

 

The problem is, is that you are presenting them w/a problem that they can not duplicate. They get the vehicle when it is running fine, w/a misfire code stored. They are going through a normal logical process of catching up the over due maintenance first.