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?
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2004 Pontiac Montana Question: Why wont my 2004 Pontiac Montana shift into passing gear?
Answer #1patrick mannion from Greg Solow's Engine Room, August 10, 2011, 21:43Master
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ReplyDanoh, August 11, 2011, 06:01Rookie
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.