Catalytic Converter for 1998 Toyota Corolla

My engine check light came on and I took my 1998 Toyota Corolla to the dealer. It has 150,000 miles on it. I just had an oil change 3 days before and it seem like every time I take it in for an oil change, there is always something else they come up with. The diagnostic check read P0420, so the dealer said I had to have a new catalytic converter installed. He also said that my timing chain tensioner needs to be replaced at the tune of $1,235.00. He also told me that I could drive it around with the engine light on and when I decided to get it done, then I should make an appointment? I made the appointment right there and then decided to just have the timing chain tensioner installed. This would cost $110 installed. I just figured after reading some of the discussions here, that I should wait on the converter and maybe take it to someone else or have the dealer reset the check engine light after they do the installation of the timing chain to see what happens. I keep the car well maintained. Any thoughts on this?

You need to find a mechanic who will read the signals from the O2 sensors to be sure of what needs to be replaced. It could be the converter, an O2 sensor or just an exhaust leak. Testing should be done. The codes don’t say directly what needs replacement.

Honestly, I’d take it to a reputable independent shop to get the exhaust work done. Without knowing if the dealer went beyond just reading the code in his diagnosis I’d be reluctant to comment on whether you’ll end up needing a cat converter, but if you do you should be able to drop that $1200 price down to about $400 to $600 installed.

Dealerships charge a fortune for cat converters.

Thank you!

Here are some of the things the mechanic should check when the trouble code of P0420 shows up http://www.obd-codes.com/p0420

How did they know you needed a new timing chain tensioner? the price doesn’t sound right.remove the front cover,install a new tensioner all for $110.00 parts and labor,the part has to be $50.00 that leaves less than a hour labor. Are you sure he did not say serpentine belt tensioner? (does your car use a serpentine belt?) I have never looked.

In the early part of your post you quote $1235.00 for the tensioner.

Hi, thanks for the input. The $1235 was for both the tensioner and catalytic converter. The service advisor quoted me $1,125. for catalytic converter and $110. for the timing tensioner, which came to a grand total of $1,235. for both. Regarding the tensioner, it says on my service report: Needs timing chain tensioner part #13540-22020, $110. installed. Verbally, he told me that this timing chain tensioner had a “slight oil leak” and that needed to be taken care of, but I could let the catalytic converter go for now. This is a Toyota dealer. They just did a 150,000 mile maintenance service on Jan. 12, 2009. Thank you