Just returned from Jaffarian Volvo in Haverhill, MA after service for check engine light - emission control system at 50k plus miles. I won't list details but I keep going back to this dealer because they do try to treat me right. Thank you, Scot.

I have the same problem on my 1999 s80 (check engine w/ emmission warning). What was the solution to the problem and the cost. thanks

Check engine light coincides with message you receive on the dash computer. Emission control system problems can range from an easy to replace sensor for a small amount of money to more difficult to access sensors for much larger bucks. In my case, an O2 (oxygen) sensor failed. Dealer has to read the codes to determine exactly what sensor(s) has failed. In my case it was a repeat failure and covered under dealer warranty for previous work. Could have cost me hundreds of dollars, however.

Interestingly - there were several other cars in the shop with same problem - emission system sensors.

A car expert, whose lecture I attended, insisted that many O2 sensor failure indications, that cause the check-engine light to come on, are due to vacuum hose leaks.

Thanks Bob -

My problem happened right at 48k miles. They thought it was a computer glitch and it would go away. Now they tell me after 50k its a sensor that would cost me $300+ to replace. I'm debating whether to replace as it doesn't effect the performance of the car nor is it a safety concern. Interesting enough the error message comes and goes. Any other probems with your car?

Why won't they fix it under warranty if it started at 48k? My initial reaction was same as yours but my state has tough emission inspection laws and I probably would have failed next inspection. I've had lots of extremely annoying problems with this car and has cost me much time off work but not too much money (so far). My conclusion after 3 years is that Volvo just doesn't have a clue how to treat a luxury sports car owner/buyer. They should have stuck to tree-huggers. Next car is a Mercedes or Audi.

Many times when you get the "Check Engine/Emissions Service Required" warning, it is due to a loose seal on the gas cap. The message then goes away by itself. Either be sure the cap is on really good (I turn it to 5 or 6 clicks), or you can put a thin film of grease on the rubber gas cap seal, or even replace the seal itself.

My local dealer says that they get a lot of these types of complaints from customers. The tell them about the gas cap thing, and if the message persists or keeps coming back, then they have the customer come back to have their ocdes read on the VADIS.