Tech, 01 non-turbo S80, I took a swag and replaced the MAF Sensor once I got the check engine. About a month ago a cleaning took care of the rough idle. Eventually returned so I replaced it. Problem is it is still idling rough and the check ehgine light did not reset it. Question is, will it on it's own or does it take a reset at the dealer?

 

I got auto zone to reset mine. If still running rough have you checked your coil packs? I have an 01 S80 non turbo my coil packs started going out at about 95,000 miles. To save yourself a lot of grief go ahead and replace all 6 of them at the same time as mine would go out about 4 weeks apart finally replaced the last 3 at one time and solved the problem. Replaced my MAF sensor but never really idled rough with a bad MAF but those coil packs will sure run rough at idle Seem to go away with some speed

 

I am watching your post with interest. Same car, same year, same CEL light....cleaned the MAF sensor, light still comes on.....car runs fine. Exhaust system checked for leaks...OK.

I have heard that several drive/stop cycles can make the light disappear (assuming that the MAF sensor was throwing the codes)....Before I replace that part (having cleaned) I plan to erase the code and do several cycles.

Frustrating isn't it ?

 

Best is to just have the codes cleared.

 

As it turned out there was in fact a bad coil, No#3. Dollars restricted me to only replacing the one for now and having the check engine lamp reset. Once I pay off the Fed (15 Apr). I'll get the others. Do you know if a special tool is required to replace the coils and just where are they located?

 

You need a torxes 30 to remove the top black cover and you will see the coils. A 10MM bolt holds them in.