The car loses power when I push the throttle down to try to go into passing gear or when trying to throttle up more power when going up a hill. It feels just like you are applying the brake while holding the throttle down at the same time, it just starts slowing down and "surging". It shifts from first to second, and to third without any problem on level ground, but when I push the throttle all the way down to accelerate, it will just bog down. A local garage has replaced the O2 sensor, the throttle sensor, the fuel pump, dropped the exhaust to check for any blockage, fuel pressure is up to specs, air filter is okey, but none of this corrected the problem, and it is still giving a code of "heated O2 sensor", according to the mechanic, and they dont know anything else to do (they did not charge me for the work, since it wasn't repaired). They also said the transmission was not giving a code. The engine runs smooth, no misses when it starts slowing down . I held the throttle down all the way to see what it would eventually do, it just slowed down and you could feel the van surging. When I let up on the throttle, it began to slowly pick up speed. Any ideas?
Why wont my 2004 Pontiac Montana shift into passing gear? on 2004 Pontiac Montana
by Danoh in Tazewell, VA on August 10, 2011
1 answer 2 comments
ANSWER by patrick mannion , August 10, 2011
It's nice of them to be honest and admit they are stumped. I enjoy getting a challenging car problem and get the satisfaction of fixing the car. There is a professional service called Identafix. http://www.identifix.com/info/about_us.htm They only deal with professional repair shops. They are in the Minnesota 651-633-8007 begin_of_the_skype_highlighting 651-633-8007 end_of_the_skype_highlighting. Your auto repair shop do all their diagnosis tests, and discuss your problem with a team of professional technicians great service cheap and very bright people. If the repair shop that are repairing your car are stumped this is a great service. This company only deal with automotive repair shops and don't answer questions for the general public but are an amazing knowledge base.
COMMENT by Danoh , August 11, 2011
Thanks for this info. I called a local AAMCO Transmission shop also, but i would have to pay $50.00 to $80.00 just for diagnostic tests, depending on what they find. I dont want to keep spending on tests. I am going to change trans fluid and filter next. I will pass this info on to the repair shop. Thanks again. I was hoping someone out there with this particular vehicle has had the same problem and had the solution. Thanks again.
COMMENT by Timberpgh , May 28, 2014
I'm having the same problem, what ya find out?