Cat. Converter Question.
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Cat. Converter Question. I know that my cat. converter is going bad, and I just bought my new car used. It's starting to choke up quite a bit before starting, doesn't start right away like it used to. I'm thinking that the bad converter could be causing a little back pressure or something that is causing this. I'm getting very worried as I spent all my money on this car, and do not know much. I'm 16 and do not have the experience really. In addition, I was wondering what some of your opinions are on what is giving me a hard time starting it...
my opinion is you're misdiagnosing the problem, if the car has a hard time starting then the catalytic converter has nothing to do with it. There is no pressure in the exhaust when you are cranking the engine via the starter, there is no combustion happening yet.
If it was the catalytic converter being clogged and restricting exhaust flow, that would manifest itself by a reduction in power when the engine is running (not when starting) especially when under load and at higher rpm, because that's when exhaust flow & pressure would be at it's highest. So if the engine runs ok around town and on highway under light load but seems to bog out under high rpm high load then that may be caused by a bad cat.
if the service engine light and codes that are being thrown are for catalytic converter, that doesn't mean it is just that, you have to diagnose the problem correctly. There is a front O2 sensor before the cat and an O2 sensor after the cat on each side. If the rear O2's are bad that might be what's throwing your code, the front O2's as well. And the O2's have nothing to do with starting the car, so if it takes longer cranking time before the engine will fire then that's some other problem, possibly the idle air control (IAC) valve. What's been done to the car prior to you getting it?
you also should've posted this in the general repair section,
If it was the catalytic converter being clogged and restricting exhaust flow, that would manifest itself by a reduction in power when the engine is running (not when starting) especially when under load and at higher rpm, because that's when exhaust flow & pressure would be at it's highest. So if the engine runs ok around town and on highway under light load but seems to bog out under high rpm high load then that may be caused by a bad cat.
if the service engine light and codes that are being thrown are for catalytic converter, that doesn't mean it is just that, you have to diagnose the problem correctly. There is a front O2 sensor before the cat and an O2 sensor after the cat on each side. If the rear O2's are bad that might be what's throwing your code, the front O2's as well. And the O2's have nothing to do with starting the car, so if it takes longer cranking time before the engine will fire then that's some other problem, possibly the idle air control (IAC) valve. What's been done to the car prior to you getting it?
you also should've posted this in the general repair section,
