low reving and losing power

[miximup]

First of all guys heloo to u all,iv got a 2.0 tdi signum ans its a 2004,over the last 4 months iv had a problem and its getting worse after a whil of driving the car it seems to rev on its own without any one touching the pedals its been to vauxhall garages now at least 7 times and they can seem to find the problem and say no codes are showing up,it soon started to cut out and i recorded it on my camcorder and sent it to the garage with the car,last week vauxhall replaced the fuel pump ,rocker and vacum pump well today it started reving on its own again and twice on the motorway it lost all power and we were almost hit by a lorry going round the roundabout.i went bananas at vauxhall and they told me to bring it in so i did and the codes were clear with no problems.it revs between 500 to 1000 continously without the accelerator being touched.my fear is that if it stalls again when driving me and my family could be killed.do u guys have any ideas,no engine lights come on when it happens.
THANX in advance

[veccy22]

is'nt there any dash lights on ? engine check perhaps ??

[miximup]

no lights at all come on it just seems to happen on its own ,i was driving from belfast to dublin when it started juddering and lost power i had to pull over quickly and almost ended up in a ditch. then todat it did it again and with the kids in the back as i was going round the roundabout im in wales at mo visiting family.iv got to take it back to vauxhall in belfast as the place here in wales couldnt find anything wrong with it. sorry about the poor typing my nerves are shoot to pieces at mo.

[miximup]

does anyone have any other suggestions to what it could be causing it.

[MysteryElite]

Complete guess here, but the throttles on these are electronic, and I wonder if you have a problem with the sensors or senders? May be something to get Vx to check out.

[Adam]

Having the same problem with mine, as are a lot of people on this forum. Take it to the dealer and get them to run the diagnostics.

[george]

Worth checking exhaust is not blocked. If the engine cant breathe properly it will only rev low and even cut out due to suffocation. Silencers can fail with loose baffles/ debris from failed cat.

[miximup]

Thanx for the info guys it happened 3 more times today and now it sends out black smoke when its reving before cutting out .

[george]

Could still be a partially blocked exhaust chocking engine so it cuts out.

[miximup]

it seems to happen after the car has driven for a couple of hours,it just happen again a few minutes ago.