Greetings all. I had my timing belt replaced, and ~100 miles later the check engine light came on. Took the car back to my mechanic, and he said that it was a bad O2 sensor. Went to autozone and got the following OBD II Codes: P0340, P0135, and P0136, which when translated means that there is a problem with the O2 sensor, and with the cam sensor.

Could it be that the timing is a little off, which makes it so the cam sensor is unhappy, and so is the O2 sensor?

If your timing is off, so are the exhaust gases. But will the mechanic fess up to doing a booboo?

Klaus
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98 V70Rawd(101Kmi), 95 854T(85K mi), 75 164E(173K mi)

off a tooth or so on a cam when he did the belt. Klaus is right....after only 100 miles from his work the sensors finally recoded as the mixture is now wrong....toooo much of a coincidence. He needs to go back in and recheck he aligned the cam pulleys correctly!

Thanks Klaus and Masher,
I was going to check the timing myself, but it doesn't seem to be as easy as it was on previous cars I've owned. Now comes a related question: could the timing being off cause there to be oil blowby which could cause a vacuum hose to pop off? This happened after the most recent time I took the care in to the same shop for a new steering rack. I know the rack repair shouldn't have caused it, but could the timing being off have caused it?

Thanks again!

--Ben