How do I know the catalytic converter failed on my honda accord 1999?

The dealer is asking for close $900USD in Dallas Texas. The engine indicator went on today and I immediately took it to the dealer, they told me they did some tests and indicated that it was the catalytic converter, my car only has 70,000 miles. Any insights? How can I really tell if the problem is the cat converter and not that the engine needs new spark plugs?|||check engine light will come on with a p0420 code.|||Usually if there is a problem with the catalytic converter, the car will heat up after being driven for a while, and exhaust will not be able to escape through the tailpipes so it will come out from under the hood (which is what heats up the engine in this case)... that's if it's actually blocked. If it's not blocked, I have no idea how else it could 'go bad'. A catalytic converter is not necessary on most cars and is only added to prevent the car from giving off environmentally damaging emissions. Find out if your car actually needs this part in order to run and if not, if the car isn't overheating, I don't see why it needs replacing... maybe someone can just chop it off and put a plain piece of pipe there, unless you live in a place where they still do yearly emissions testing in the US. Just don't tell anyone you've done that; it's technically illegal.|||i would get a second opinion. and if the ct is plugged the car will be sluggish and have no power|||Take your car to the local autozone and have them scan your computer, the code for a bad cat converter is P0420...... see what codes come up.... $900 is an extreme rip off for any car.... you can get a direct fit cat converter from magnaflow for $50 and pay $75 to have it installed, I paid $40 to have one installed, so I paid $90 all together for one installed on my Durango.|||Ditto chris's answer.





stampy friggin skunk doesn't have a clue!!!!!!





USED converters are going for 100's of dollars on Ebay.


They have palladium, rhodium, and many other precious metals in them.





If you put a "direct (piece of junk) fit" converter on your car you may as well throw the money in the garbage.





Most likely the light will return with the same code in short order.





If it has a CAT code on a Honda.................it needs a CAT.|||It is possible that there is a small exhaust leak near at one of the flanges that could also cause this. At 70k, the cat usually doesn't go bad on the hondas. I'd have the exhaust system checked for leakage first. If the light goes out after a while, it's probably a leak somewhere.


FYI - you can drive it like that and you won't notice anything except the light. But when it comes time for emissions test, it'll need to be fixed.|||All OBD II cars (1996 and newer) have a oxygen sensor downstream of the catalytic converter to test cat operation. The computer varies the air/fuel mixture from slightly lean (more air than optimal) to slightly rich (more fuel than optimal) The upstream O2 sensor(s) will see this "cross counting" and relay this information to the computer. The downstream O2 sensor, if the cat is functioning correctly, should show a constant O2 content, with no cross counting. If the cat isn't working correctly, the downstream O2 sensor will see the cross counting, and set a code and illuminate the check engine light. Barring any electrical faults in the downstream O2 sensor circuit, if the code described above is set, the cat is probably bad. Spark plugs will have no affect on this code.





Edit: If you remove the cat, the code will stay on, and when you get your smog test, it will fail automatically just for having the code, whether or not it passes the tailpipe test. DO NOT DISABLE EMISSIONS EQUIPMENT! It's not only illegal (federal law, so it doesn't matter where you live) but it DOES have an affect on how much your car pollutes, and breathing smog sucks...