Throttle Sensor or Turbo Control Valve on 2002 Volvo V70 XC

Today I was driving down the highway when my acceloration stopped. When pressing on the gas, nothing happened. My car will coast at no more that 5 miles an hour, but will not accelerate at all. All systems were operating at normal. No codes no lights. After turning the car off and letting it set for a few minutes, I restarted it and the car responded as it should, but I now have a engine service required light on. Stopped by advance and 4 codes were spit out. PO-234, P2-127, P2-122, P2-121 Any help would be appreciated!! :)

by in Danville, WV on October 29, 2010
2 answers 1 comment
ANSWER by on October 29, 2010
These are ETM (Electronic Throttle Module) and APP (Accelerator Pedal Position ) sensor codes. I think the recall is not valid for your car since it's 2002 model, but check the label on the throttle module. If the label is white it's still the first generation ETM and you might have a chance to get the problem resolved for free. The car needs a real scan tool, VIDA or DICE, which are the OE diagnostic tools, so you need to take your car to an independent Volvo shop who has one, or to the dealership. Generic scanner can't read Volvo codes correctly, I have seen many misdiagnosed Volvos by non OE diag. tools. If the above codes will be confirmed, the car might need an accelerator pedal position sensor or an ETM. Zee
COMMENT by on June 03, 2012
The only 2002 models that had the [problematic] Magneti Marelli throttle body were the early carbureted (non-turbo) models. This turbo car will have the Bosch TB. Agree completely on using the VIDA/DiCE diagnostic tool to get the real Volvo codes. Some shops will do it for free and many will charge you a fee -- so long as it is for your own car. I'm still betting it is a clogged fuel filter and these are just sympathetic "downstream" error codes.
ANSWER by on June 03, 2012
234 is an over-boost event. It could be the TCV - they do weaken and/or fail but that usually results in under boost. It sounds like you might very well just have a clogged fuel filter. It happens with cars this old and simply throwing cleaner in the fuel tank can actually make the problem worse by freeing up other contaminants that get caught in an already clogged filter. Also make sure that your air intake is nice and clean and no vacuum hoses are off or leaking. These things are easy to check and inexpensive to change at your local oil & lube place or by a DIYer. That's a pretty simple and inexpensive way to start. If that doesn't fix the problem then you probably need someone who has the instruments to test the various turbo and fuel delivery components.