V8 Vantage cuts out at full throttle only

[samastonlongley]

I’ve been in the process of trying to cure a fault on my Vantage. I went to the car a while back and it flagged up DSC Service Required and Traction Control Disabled etc. I initially thourght this could be an ABS fault. In between time my clutch started to fail so my 2006 V8 Vantage was of the road for a few months whilst I replaced my clutch for a twin plate one from AMR. With the new clutch fitted I took it for a drive and all was well apart from the DSC And Traction Control warning light been on. Took to a local ECU Tuning specialist who I have used before and always found very good who put the diognosics on it and found that one of the sensors on the actual accelerator unit was reading 96% all the time. I ordered a new pedal from BR and fitted it and as soon as it was plugged in and fitted it cleared all the fault codes! The car then went for an MOT and because it had been stood a while I wanted to give it a good run to get it nice and hot for the emissions test. However as soon as I went for full throttle the same DSC lights and TC Temporary Unavailable lights came on, the engine cut out and it went into fail safe mode. Pull over, turned it off and back on again and all was fine again..

I’ve had it plugged into my own code reader and I can see both sensors working and I can see the throttle position sensor working so that to me proves the sensors on the pedal and TPS is all working. I’ve since sent it back to my local guy and he’s in agreement that now with the new pedal fitted the sensors are all working but he can’t see anything that would put it into safe mode. As soon as you floor the pedal you can see the throttle body snap shut as it goes into fail safe mode and you can also watch the TPS read 0 when the pedal is fully depressed. Does anyone have any similar experiences or perhaps know what causes it to go into safe mode? If not I think it will have to sent down to BR but it’s 200mile away from me so I’m trying to get an idea of what’s wrong before I send it down there.

Many thanks
Sam

Edited by samastonlongley on Tuesday 22 January 14:25

[akita1]

Hi Sam I had the dsc light come on after hitting a pothole I had several people look at the car attempting a cure but with no luck I took it into Pugsley and lewis in Beckenham who traced the fault to a sensor which I believe is under the brake master cylinder cost was around £80.00 for the sensor and was just a fluke that it expired at the same time as the pothole incident.

[akita1]

Hi Sam I had the dsc light come on after hitting a pothole I had several people look at the car attempting a cure but with no luck I took it into Pugsley and lewis in Beckenham who traced the fault to a sensor which I believe is under the brake master cylinder cost was around £80.00 for the sensor and was just a fluke that it expired at the same time as the pothole incident.

[john ryan]

RTFM, as they say. At full throttle, the engine will not fire. This is to permit oil to circulate as the engine spins on the starter, so as to obviate oil starvation after a long lay-up. If you have a problem, this is where the fault lies.

Edited by john ryan on Tuesday 22 January 15:39

[samastonlongley]

akita1 said:

Hi Sam I had the dsc light come on after hitting a pothole I had several people look at the car attempting a cure but with no luck I took it into Pugsley and lewis in Beckenham who traced the fault to a sensor which I believe is under the brake master cylinder cost was around £80.00 for the sensor and was just a fluke that it expired at the same time as the pothole incident.

I’ve read about this sensor before and I initially thourght it was that when the light first came on or perhaps an ABS sensor but since fitting the new pedal the light has gone off and the car drives fine with no warning lights it’s just when I got for full throttle it goes into fail safe mode and then the DSC lights come back on, as soon as I turn it off and back on again however the lights are gone again and the car goes back to normal, until I go for full throttle again..

[leman600]

Hi Sam. It could be that the sensor has to be taught limits or configured in some way to the ECU. It's only a guess but it could be that full throttle goes out of range to a plausible value or something. Measure the value through nil to full throttle and see if makes sence. May be at least a logical and cheap place to start.

[Manx V8V]

akita1 said:

Hi Sam I had the dsc light come on after hitting a pothole I had several people look at the car attempting a cure but with no luck I took it into Pugsley and lewis in Beckenham who traced the fault to a sensor which I believe is under the brake master cylinder cost was around £80.00 for the sensor and was just a fluke that it expired at the same time as the pothole incident.

This is the brake pressure transducer, a fairly simple DIY swap, it causes the lights as described, but not as far as I'm aware the throttle problem.

[samastonlongley]

I might be wrong but I don’t think it is the brake pressure switch as the DSC light and TC light was only on with the old pedal fitted. Once the new pedal was fitted all these faults disappeared. However with the new pedal cures the existing fault it seems to have caused a new fault which is this going into fail safe mode and cutting out at full throttle.

[samastonlongley]

Thanks for people’s help on this topic. I managed to get the issue sorted. Turns out on the newer pedals, the post recall pedal, the plugs are on the opposite way round. We swapped the plugs round and so far so good!