Hi Everyone,

Model : S80 , T6 2.7Lit 1999
KMs: 169,000 Approx.

I had this car for 7-8 months with no issues and running smooth.

All of sudden,one cold day engine started rattling, RPM drop down all of sudden to less then 1 and transmission light came up on the dashboard.

Following day took this car to Volvo authorized service agent. Hooked up the scanner to vehicle to check faults.

Faults traced are Air flow meter, boost switch sensor, broken breather hose and throttle body issues.

- Air flow meter is replaced with new one.
- Boost switch sensor replaced with new one.
- Breather Hose replaced with new one.
- Thorttle body is also replaced (new Volvo S80 thorttle body recommend)
Then car is towed to Volvo Car service for software upgrade.

Car is running as smooth as brand new car for one day.

Next day its started doing same RPM drops down and Car doesn't move at all, after 1-2mins it runs normal.

Transmission error on the dashboard came back and now even shows immobilizer error message "immobilizer check manual".

Now sometimes my car doesn't start up at all.

Do anyone suggest me what need to be done to fix this issue?

is it software compatibility issue?

Anything to do with immobilizer?

I have checked fuse for the thorttle body its fine. tested other fuses they are working fine.

Any suggestions or views on the issue please?

Thank you