Scotty,
My wife has a 2003 Pontiac Vibe automatic AWD base model with 267K. Motor runs great. Just recently the car lost power and couldn't climb small hills or rolls in the highway. Summiting a pass the car was in first gear and high revving doing 25mph. On the flat the car does fine out of first gear, but in second gear its gutless. Once in high gear it runs just fine provided it's flat road. There is some exhaust noise (I think) from under the hood area. There's no code showing. The dealer couldn't find the problem and suggested it needs a new cat (for major $). I tried your lacquer thinner method. It increased the power a little bit, stopped an odor the car had at start up, but the power/torque hasn't returned. Is it a cat? Or maybe a transmission problem? Hate to sell the car as the motor seems pretty bullet proof and the body is still in good shape. Should we pay to fix it or get another Vibe?
Thanks Scotty
The dealer couldn't find the problem and suggested it needs a new cat (for major $).
There are no Pontiac dealers any more, so what dealer did you take it to? Toyota?
Aside from the fact that dealers are the most expensive place for service and frequently rip people off, that is a 20 year old car. You can bet that most of the dealership technicians were in diapers when it was built and they have no experience with it. It would also seem that the dealer you took it to is incompetent because an exhaust restriction from a clogged catalytic converter is easy to test for and they were apparently just bumbling around and guessing.
Stay away from the dealer and find a good local mechanic who can properly diagnose the problem. (Also stay away from chain shops like Pep Boys, Midas, Firestone, etc.)
I tried your lacquer thinner method.
You should not have put lacquer thinner in your gas tank. The video you're referring to is about a dozen years old and is out of date. Since then lacquer thinner has been found to attack and damage fuel system components. If you want to clean your catalytic converter use a purpose-made product like Cataclean.
What is there method that a DIY mechanic could use to test if it is indeed the cat?
You'd need to buy a back-pressure gauge that screws into the upstream O2 sensor port. (You temporarily take the sensor out and the engine runs open loop while testing.) Looks like Amazon has them for about $43.
https://www.youtube.com/watch?v=qJTmddbOxMk
https://www.amazon.com/dp/B09WTZRL8N?th=1
IMHO, just anecdotally, it seems like the car needs to be replaced. I had two cars with similar trouble going up a hill. Got the code for the cat. And it ended up being the cat.
Don’t go to the dealer for that unless that is the only choice in your state.
Theoretically speaking, you could bolt off the car momentarily to test it. Or straight pipe to test. Not sure if that is legal to do in your state from testing purposes. I don’t recommend breaking the law.
