Volvo V50 throttle problem?

[uktrailmonster]

My V50 2.0d has recently developed an odd fault. In 5th and 6th gear at around 60-70 mph I can sometimes feel a vibration (for all the world like an out of balance front wheel, but it must be engine related) and then the throttle cuts out into a 'safe' mode only allowing part throttle. When I re-cycle the ignition everything is fine again. I'm wondering if it's a dodgy throttle pot or some other electrical gremlin. Anyone had a similar fault with these cars and what was the diagnosis? Mileage is 95K and it's been faultless right up until now. It's an intermittent fault (although getting more frequent) and the engine is fine when it's behaving itself. Which points to an electrical rather than mechanical issue.

[uktrailmonster]

I guess it's not that common then.

[uktrailmonster]

pmjg66 said:

need to get the code read,this will give an indication.

worth checking the fuel and air filter for blockages.

there have been problems with egr valves,turbos,particulate trap sensors.

Thanks for your thoughts. I can't see it being any of those as the problem clears instantly when resetting the ignition. Been reading on forums about inherent problems with throttle body sensors although it's not clear which models are affected. I think this is likely to be the problem. Think I'll have to take it to the main dealer and get it checked.

[uktrailmonster]

krystalonyx said:

Uktrailmonster, did you get this problem fixed?

I have just bought a V50 and the particulate filter has been chan ged and the engine still goes into 'safe' mode.

Can you advise??

I'm still living with the problem I'm afraid, but it is going in for a full service in the next few weeks (Volvo indy specialist) and I will get them to investigate and hopefully cure. The problem hasn't got any worse, but it still goes into 'limp' home mode every now and again - it seems to be provoked most often when cruising at about 65-75 mph and then demanding high throttle eg. when going up an incline or accelerating to overtake. It then starts to vibrate (like a wheel out of balance) and then finally goes into 'limp' mode. But if you back off the throttle slightly as it starts to vibrate you can push through this zone and then it continues to accelerate normally as the engine revs increase. I'm getting quite good at that now! Rarely happens when driving on slower A/B roads. I'm thinking it must be something to do with the throttle position sensor given the symptoms. It doesn't seem to be mechanical at all.

Will let you know when the garage has diagnosed it.

Edited by uktrailmonster on Thursday 12th January 21:03