Advice Needed On O2 Sensors & Catalytic Converters


Question: Advice Needed On O2 Sensors & Catalytic Converters,
I have a 2002 Mazda Protege ES. Recently the check engine light came on so I had the code checked at Auto Zone. The code came up as: Warm up catalyst threshold below bank 1″ which apparently indicates a problem with either the oxygen sensor or the catalytic converter– or possibly both. If the check engine light didn’t come on, I would have never known anything was wrong with the car– it performs just fine. I took the car to two different mechanics and both want to do different things. First one said both oxygen sensors were bad as well as both catalytic converters. He wanted to charge me $700. just to replace the oxygen sensor. The other said a good place to start would be ordering and installing the oxygen sensors… it won’t hurt the car if they are bad. Then wait to see what happens to the catalytic converter and if I start to have problems then replace it. Which should I do? Like I said before, the car runs just fine. Right now I am saving up the money and plan on replacing (the catalytic converter) in about 2 weeks (next pay day). Is driving my car like this okay until then?

I need to take two trips this weekend out of town and don’t want to get stuck. Each trip is 25 miles one way.

Best answer for Advice Needed On O2 Sensors & Catalytic Converters

I’ve NEVER had to replace a catalytic converter or oxygen sensor on any car that I’ve owned since 1985. Get another opinion. Each oxygen sensor has it’s own trouble code, so you should only replace those that are coded.

NAPA auto parts sells oxygen sensors for about $139 retail So, $700 to replace the oxygen sensor is bull. All it takes is a socket wrench to remove and replace.

The mechanics you went to know what’s wrong, but won’t tell you. They want to take you for all you have. There’s no way that all oxygen sensors and both catalytic converters are bad.

This site: http://www.miata.net/garage/obdii.html doesn’t list anything that says “warm up catalyst threshold…” Take it to another AutoZone or Checker or another place and have the codes read again.

You’ll be okay driving your car.

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  1. Richardnixon08
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