Hi,
I currently own a 2010 C30 T5 R-Design automatic.
The engine performance reduction message has popped up a few times in the last couple of months. Thankfully no other engine or warning lights have come on.
This only started the day after having a new front tyre fitted and has happened 3 times since. Is this just a coincidence? Turning the car off waiting a minute and restarting seems to reset it.
The wheels have been off for new brakes and new LH mount fitted since the new tyre was installed.
There doesn't appear to be any info in the owners manual about this messsge so any thoughts or advice on potential cause and fix would be greatly appreciated please?

  • Major Ledfoot replied to this.
  • Finally sorted. Various throttle body and accelerator pedal positions codes being thrown.
    Accelerator pedal replaced, throttle body cleaned out and codes have not reappeared.
    Thanks for the advice everyone.

    Have the codes read by VIDA and DICE scanner or high end generic scanner.

    I agree, you'll need to read the codes from the OBD2 port with a scantool first. The only sensors I can think of around the wheel well is for ABS but I think you would get the ABS warning light if that had failed.

    Thanks for the replies. The first time it happened after getting the tyre replaced the ABS light also came on but then disappeared. Was able to get it to the Volvo/Euro workshop today that we always go to and appears it is throwing a code for the accelerator (I wasn't there so third hand info) . Booked in for new year to sort it out. I'm assuming they cleared the code as they said should be fine for now. Thanks again for your help.

    Do you have a sunroof? Accelerator faults on P1 chassis volvos are usually CEM related, as the signals (analog and digital) pass through CEM and then onto ECM. If your car has a sunroof, the drains can leak onto the CEM causing corrosion otherwise the connector pins themselves can lose tension.

      timbo thanks Timbo. No sunroof on this one. Is this a common C30 T5 issue? I've owned an 01 XC70 T5 and an 07 XC90 T5 and not come across this before.

      NathL The wheels have been off for new brakes and new LH mount fitted since the new tyre was installed.

      LH engine mount? Subframe mount?

      @timbo - is there any harness connector in the region of the LH engine mount that could be disturbed by replacing it?

      (taking an interest in this topic because wife's Ceres = 2012 C30 T5 auto)

      a month later

      Finally sorted. Various throttle body and accelerator pedal positions codes being thrown.
      Accelerator pedal replaced, throttle body cleaned out and codes have not reappeared.
      Thanks for the advice everyone.

        Ex850R yep always used 98 in the Volvo's I have owned. But have heard there is a difference in quality between brands.

        Hi. A little late for you but I had a similar issue with an S40 with the 2.4i engine. Got the same message coming on and off and felt performance was sluggish when accelerating ( Had only just acquired car at the time and thought it was because it was a non turbo but the lights in dash made me think. Mark at Voldat worked it out though. Turned out that the electrical connectors for the accelerator pedal were corroded/ dirty. He cleaned them up and have never looked back.