Subaru Forester Catalytic Converter

I have a 2000 Forester with 53,000 miles on it. Check engine light came on, and codes indicated converter problem. Mechanic erased codes and re-set to confirm that it wasn’t just a glitch. Light came back on. Isn’t 50,000 miles too soon to need a new converter? Anyone have any experience with this? If I do need a new one, is aftermarket converter reliable?

Converter codes are usually O2 sensor code. The O2 sensors are either saying the catalytic converter is bad or the O2(s) need to be replaced.

Anything can fail. In your case, the Cat should be covered under warranty though. It’s part of the emissions control system, and almost always covered separatly from the drive train an other components (check you warranty paperwork). As far as aftermarket, sure, go for it.

It’s the way the ENGINE runs that affects the catalytic converter. Does the engine run a little rough, sometimes? When an engine runs rough, and misfires, unburned fuel goes into the catalytic converter and can cause it to get very hot, from burning that fuel. Replace the spark plugs to get a smoother running engine, and a healthier catalytic converter.

Federal Emissions Warranty covers your catalytic converter up to 80,000 miles with no deductible. Have the dealer install an OEM converter since it will be free. If the problem is something else at least you will not have had to spend any money to discover it.

The warranty is 8 years or 80k miles, so it may have expired depending on what month it was built.

Subarus from '99 to '01 have common convertor failure. There also was an update to the front oxygen sensor (now referred to as an A/F sensor). They might insist on updating the sensor first. Just make sure it’s documented in the paperwork that it may need a convertor if your car is still under warranty. That way you don’t have to worry about the warranty expiring if the light returns later. You’ll be protected.

Thanks–checking with Subaru to see when it first sold at retail–it may have missed the 8 year cut-off by a couple of days!

An engine which misfires and runs rough can knock out a healthy catalytic converter. If your engine isn’t running smoothly (especially during acceleration), change the spark plugs and the air filter, for starters.

This is the same problem I’m having w/ my 2003. I’ve had the light reset several times and changed the O2 sensor. Thanks to all for the post about the emissions warranty. My mechanics never mentioned anything about it! The want to charge a fortune to put a new converter in. And I was ready to do it. Glad I listened to my daughter and looked here first.

What are you going to do when that catalytic converter starts having the same symptoms CAUSED BY the engine? The CAUSES have to be cured, to prevent the same results (a damaged catalytic converter).

So much for the theory that one is “always better-off going to an independent mechanic”! Clearly your mechanic wants to make some money from you, and as a result, he has conveniently failed to mention the warranty that allows you to obtain free repairs from the dealership. In my book, that is dishonesty on his part, and I would never patronize that guy again, if I were you.

Yes, an independent mechanic may charge less for many procedures, but to assume that one is “always better-off” by going to an independent shop is a perfect example of the fallacy of dealing in absolutes.

I have done all the maintance recommended for my car. Oil, plugs, filters, tune ups, engine cleaned, etc. Maybe I just got a bad cat to start with. I also don’t put cheap gas in it. What other suggestions do ou have to avoid the problem recurring?

It would help to know what the codes are. Auto parts houses such as AutoZone, Checkers, etc. will check them for you absolutely free and it only takes a few minutes. You might consider getting this done and posting the results back here for further discussion.

You may be a bit iffy on any warranty coverage. The warranty period starts on the day the vehicle was first put into service; either when you bought it new (as in 4 or 5 miles on it) or if it was a dealer demo the day that it was first put into service as a demonstrator.

If you do need a new converter there is nothing wrong with an aftermarket converter and it will save you some money over the Subaru OEM converter.

Converters can also be killed by other things; chronic rough running, too rich on the fuel mixture, coolant seepage into the combustion chambers (head gasket weepage, etc.)

It’s great that you do the routine maintenance to keep the engine healthy which will help to keep the catalytic converter healthy. The catalytic converter failure (IF it has failed) would be from things you have no control over, most likely. You say you CLEAN the engine? Do you shine up the hoses and wires with something like ARMOURALL PROTECTANT, or other SILICONE spray? Silicone can be drawn into the engine air intake (where is the engine air intake opening?), go through the engine, and be deposited on the oxygen sensors and the catalyst…poisoning both.

The engine computer uses inputs from the oxygen sensors to determine the health of the catalytic converter. Who checks the health of the oxygen sensors, which would ensure that they are “telling the truth”? A mechanic should be able to do that. If the oxygen sensors, themselves, are unhealthy, they will be wrong about the health of the catalytic converter.
Here’s a little article to explain some of this: http://www.autotap.com/Articles/Intro_to_Engine_Management.html