Hi,
My 1999 S-80 T6 is acting up again. The computer shows "emission system service required" and on the other side the check engine light comes on. It stays like this for about 3 drives then the emission system service required goes out and the next drive the check engine light goes out & everything is back to normal. No change in how the car drives. Twice in the past 2 week, 2 days apart, the car following me started flashing their lights like something was wrong. Upon arrival at home, the lights work fine, the tires are fine. The shop found codes ECM-261A, ECM-271A, ECM-901E, and ECM-903F. When they found this the lights had gone back to normal the first time. It has done it twice since. The last time I drove both lights were on. Does anyone know what is going on & if it is something that must be fixed? It is out of warranty & I take it to a private volvo shop. Any info would be appreciated.
Sandy

Here are the information on VADIS:
261 - Checking fuel injection system - Check intake system for air leakage according to Check for air leaks in the intake system .

271 - Checking fuel injection system - Check intake system for air leakage according to Check for air leaks in the intake system .

901 - Replacing engine control module (ECM) and programming - Engine control module (ECM) has registered an internal fault.

902 - Checking the wiring and components - Electronic Throttle Module

Not 100% sure the cause, but if you see a message - "Stop safely and restart" in the future, it is most likely a faulty Electronic Throttle Module (ETM).
I hope it helps and good luck.

KC

I have the same message "emission system service required" and check engine light turned on. What should I do next. I would hate taking it to a volvo service place and all they do is look at it and flip a switch to turn it off. Can anyone suggest something since I am not very good with cars and I have only had this for a month.
Any help would be appreciated.
Thanks,
AP