I am an owner of a 2003 S60. A couple of weeks ago I was traveling from Waco TX to OKC, OK (about a 5 hour drive). Just as soon as I had reached OKC my check engine light appeared. I figured I would deal with it when I got home, but then on my trip back my gas mileage dropped from about 35 mpg on the highway to 25. I took the car into a local shop. Their diagnostics system could only tell me it was an emission problem that caused the check engine light. They reset it without doing any actual workand it has not come back on yet, but I am still suffering on mileage. Has anyone experienced anything like this or have any clue what I should do?

 

O2 sensor or MAF sensor could cause this type of problem. Did they give youthe code that caused the CEL?

 

no they didn't give me the code. i'm just going to go ahead and drive up to dallas tomorrow though and have the dealership sort it out. thanks though.

 

If it's not under warranty:

Many part stores will hook it up to their diagnostic equipment for free. If it's something as simple as a sensor causing you to run rich, then it's an easy do-it-yourself fix that will save you a ton off the dealers diagnostic/repair costs.

 

Well it turned out to be a leakdetection pumpin the gas tank. they also discovereda transmission fluid leak and some problems with my control arm bushings (i think thats what they said, I'm not car savvy...). Of course i got murdered on labor costs... they also told me my timing belt was marginal which adds up given the recent post on the matter. It was a transaxle seal that leaked. is that easy to replace? i'd like to know for future notice since the part was less than twenty dollars yet the labor was close to 250.