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Rough running

795 views 4 replies 3 participants last post by  Antwhitt 
#1 ·
Hi guys, I know this has probably been asked many times but it's at the end of my tether with it now.

To cut a long story short, my car started playing up about 2 weeks ago where the idle was all over the place. The car was shaking, mpg was down and it was running rich, it turned out to be the egr valve. I had the egr replaced and thought nothing of it, car ran fine.

A week later the car starts playing up again, this time it seemed to be misfiring and was down on power quite abit. I managed to get it to a friends work that specialises in vw and from then on it wouldn't start. It was diagnosed with a faulty egr valve, again, with the egr unplugged it would start and drive fine. I replaced the egr valve again and everything was fine up until one of the coils went. Not surprising as I had it serviced when it was in the garage.

After changing all the coils just to be on the safe side I got about 20 minutes driving out of it before it started playing up again. Idle was up and down again, running rich and struggling to start. It was plugged into a generic code reader that came back with egr circuit malfunction. Now surely I can't be that unlucky to have bought 2 faulty egr valves.

could it be a broken wire maybe? Maybe another sensor on the same circuit that is faulty? I don't know where to start and would really appreciate some help if anyone knows anything. Thanks.
 
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#3 ·
If your car is a TDI with the BKD engine I experienced this and pinned it down to the Anti Shudder Valve.
This is just below the EGR pipe and is part of the same assembly.
Essentially the ASV is a throttle flap designed to make the engine shut down gently.
Whatever had gone wrong on mine was throttling the engine at random intervals and would cause the car to stall mid motorway during rush hour. Really not pleasant.
Ripped the damned thing off and relaced with a race pipe from Allard.
Will have the lot mapped out in the next couple of months and put the whole saga to bed.
 
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