Year and model: 1999 S80 (2.9L)
Miles: 180K

Problem: Engine System Service Urgent + Emission System Service Urgent warning messages come on during normal driving on highway. The second message often disappears after shutting engine off overnight. The first message disappears less often than the first.

Observations: Car rides rough when messages and cautiontriangleappear. It seems like car is not burning on all cylinders. Messages appear to be related to driving speed and length of drive. Short 5-10 min trips do not trigger message but longer trips do. Commute42 miles roundtrip daily.

Questions: What is the cause of this? How can it be repaired? Volvo dealer cleared these messages once but they re-appeared within a day.

 

what were the codes? get the codes and then reply back with them.

 

When the message appears your car is going into a limp mode, that's why it's riding so rough. When it does this your mechanic can pull the codes and tell you exactly what's going wrong. I don't understand why your dealer would just clear the codes without telling you what's wrong?

I highly recommend that you don't drive the car much until you find out what's wrong. You could damage your vehicle more by driving it with a system that isn't working properly.

 

PLEASE HELP!
I recently began to see and engine system service message show up in my 2001 Volvo S80(t-charged). After some research I saw that the throttle body could potentially the problem so i took it out and cleaned it, while it definitely help the overall performance it still when not disable limp mode and I'm trying to troubleshoot the issue because I have already taken her to the dealer to get them cleared just for it to reappear 2 days later. Any other potential fixes that would help my issues ????