Catalytic converter on my friend's 2006 Chevy HHR (~220k miles) failed yet again and we're not sure why, any advice?
Several months ago, a mechanic from Midas diagnosed the problem as the result of a cracked exhaust manifold, so they fixed that and replaced the catalytic converter. Unfortunately, the catalytic converter broke yet again recently. She described this problem of barely being able to drive it up hills because she'd have her foot all the way down on the pedal and her max speed would be just 40 mph.
My friend can't take it back to the same mechanic (or even another Midas branch) because the nearest one is too far (she got it repaired while visiting family back home) and she is unsure if the car can even make it there. A service clerk for that branch also recommended just manually turning the check engine light and selling it without disclosing the problem with the catalytic converter (very ethical I know). Another local mechanic said he thinks the problem may have something to do with the computer (or something like that) but that it's not worth spending the $1200 to replace the catalytic converter because the problem may be something else entirely and it's too risky spending that kind of money on this old of a car. At this point, she's just going to get a new car and be done with this HHR, but anyone have any idea what could possibly be wrong with her car?
Midas is about the worst place to go for any kind of repair. The advice given by their service clerk gives you an idea of the company's ethics.
Engine misfiring is the most frequent cause of premature catalytic converter failure, and replacing the cat without fixing the underlying problem would certainly ruin the new one.
I certainly would not put any more money into a 17-year-old, high mileage HHR. Your friend is making a good judgement call not throwing away good money after bad.
Not a good idea to sell under the false pretense especially when pollution controls are involved. There is a record of the catalytic converter being changed. Midas has a terrible reputation. Bring it to a good mechnic you know and trust.
