2008 Hummer H3 Four Wheel Drive Automatic 26,000 miles
My 2008 Hummer H3 is having a problem with moderate pinging under load. It occurs heavily when the engine is hot and the A/C is on and I'm driving up hill. The pinging will continue and never stop. I can feel the vehicle losing power and feeling sluggish, probably due to timing being pulled to the max. Ive taken it to 2 different Hummer dealers and they acknowledge that its pinging but say their tests show that there is nothing wrong with the vehicle. The H3 is recommended at 87 octane but I have to use 91 octane to keep it from knocking. Ive tried changing the plugs, cleaned the MAF, changed the air filter, flushed radiator, changed to synthetic oil, run several treatments of engine/fuel cleaners with no results. Ive never abused the motor and only fueled up with top tier fuel brands.
have the same problem?
Thursday, October 22nd, 2009 AT 11:17 PM