Model: 2005 Volvo S40 2.4i / 5 speed automatic Mileage: 127k Miles / 3rd owner Transmission service history: not even changed ATF Other relevant services: replaced all engine/transmission mounts last month.
Hi,
I am experiencing an occasional issue when shift between R and D. Check engine light doesn't show any problem. The symptoms are:
- Delayed engagement for 1-3 sec, with slight engine rev up by ~100 rpm. Mostly when shifting to D.
- When engagement happens, it is abrupt and harsh with a bang under the engine bay, as if the vehicle is jolting.
- The problem only happened after driving for around thirty minutes. Cold start and shifting are smooth. However the problem persists after warm restart.
I asked a mechanic to check ATF, which is adequate and fresh, surprisingly. And I contacted a Volvo dealer, who says, over the phone, this is more likely a solenoid/valve body problem. He also suggest me keep driving until I need a rebuild.
Currently I am looking into the following solutions:
- Change/flush ATF
- Updare TCM
- Check/replace solenoid
Please provide your opinions about the root cause here, and how to fix it. I really appreciate the help!
