2006 RSX CHECK ENGINE LIGHT CAME ON WITH 45000 MILES. THE CAR RUNS LIKE NEW. THE DEALER SAID IT IS THE O2 SENSOR BUT I DON'T BELIEVE THEM. WHAT ELSE COULD IT BE?

O2 sensors can cause this and often they clear up after a good run.

Hi R, As the vehicle started after replacing the oxygen sensor I don't believe the two problems are linked. Have your mechanic carry out a diagnostic scan and we'll go on from there. As a matter of interest, why did you replace the oxygen sensor? Regards John

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It is surprising to me that both o2 sensors would go bad at the same time, but it could be possible. If your mechanic disconnected the battery, and installed the o2 sensors, upon connecting the battery the computer would have to relearn the cars performance again. This could take anywhere from 100- 250 miles. Don't get upset, take the car for a ride and let the computer do it's job. If this doesn't work then it is possible that one of the sensors is bad. Your computer will let you know via CHECK ENGINE light. GOOD LUCK.-

Go to a qualified exhaust shop, and have them look at the problem. It isn't hard for them to diagnose problems with catalytic converters. If they tell you the cats are fine, then they are fine. However they will tell you what is the problem. Personally I wouldn't trust either the mechanic or the dealer.

The 02 sensor is detecting a malfunction in the emissions. That would be from a bad fuel mixture, too rich or too lean caused by dirty or faulty injectors or MAF sensor. A clogged catalytic converter will also cause it. Connect a manual fuel gauge to the fuel rail and test your fuel presuure. Test your fuel pressure regulator, the fuel pressure should increase 5-10 pounds when you disconnect the regulator...if it don't, the regulator is bad...Check for vacuum leaks and stuck or dirty egr valve. This would cause a lean condition. Check your air filter. Good luck, i hope this helps.

could be a wire issue with the o2 sensor, because you hit something.

You don't necessarily need a new converter. I had this code on my 2006 Odyssey at around 150,000 miles for both the front and rear converter and only needed new downstream O2 sensors ($40 for the back, $60 for the front). This is why my car never sees the inside of a dealership shop, they're happy to replace your converter for >$1000 without even looking at the problem. A little troubleshooting goes a long way here. I grabbed an engine code reader from the local auto parts store and read the O2 sensors with the engine running and noticed the voltages on them were erratic, and they shouldn't be. Mine were reading ~ 0.8 volts, then would jump down to < 0.1 volts for a couple readings, then back up to 0.8. The downstream sensor readings should be fairly stable.

ebay for comp unit
were thyt volvo o2 sensors

Have a dealer or garage check your Oxygen (O2) sensor. As a quick fix, try disconnecting and reconnecting your car battery. Sometimes this will reset the check engine light.Good Luck!