hunting

[gRoberts]

hey everyone,

I tried to ask this earlier but I never really had any responses, so I'm going to naughty and ask again.

I've got a 2.1 TD LX that's developed an intermittent hunting that on two occasions has got very scary.

Some times, when idling, it will hunt between 1000 and 2000 revs. I've tried pulling the accelerator out with no luck and I've tried accelerating it out with no luck.

Other times, whilst driving, when changing gear, the car will stay at the revs prior to changing (i.e. when changing at 2000, it would stay there.)

On all of the above occasions it doesn't accelerate the car when in gear, but a few weeks back and yesterday, I had to kill the engine.

When dipping the clutch it would act as if I have planted my foot on the accelerator and attempt to red line. Yesterday, I tried to engage the clutch and it did accelerate the car (duh) so I had to kill the engine.

When I started it again, it hunted a little and then has been fine since.

The car's due to go on a 1400 mile trip to europe and I fancy getting it fixed before I leave. Question is, what is it ;)

This doesn't happen every day, but it has happened on a enough occasions to think there is something that's not going to go away and is likely to get worse.

Any idea's?

Cheers

Gav

[maglite1]

ide be changing fuel filter and making sure that fuel lines have no air in them revving irratic like that sounds like starvation of fuel and its getting a burst of air or an air bubble is blocking fuel line , put some injector cleaner in the fuel filter when ya change it and put rest of it in tank it will smoke like crazy when ya start car up for few minutes but will give injectors a good clean , ide also check all pipes for air leaks on inlet manifold get a can of wd40 with the straw on and when car is idling spray around anywhere a pipe connects and listen for engine tone changing its a good way of finding small air leaks. its only a guess but its the way ide be looking.

[steve_earwig]

Some of that sounds like it's running on it's own oil... Throttle pot?

[gRoberts]

Cheers lads,

Running on it's own oil? Worrying lol How would that happen?

The car had a service 2 months ago, so the fuel filter's almost brand new and at the same time it had a full course of Forte.

I'll be getting it booked in for someone to look at it but it'd be nice to know roughly what it could be before I end up handing over yet another fist full of cash.

This car is costing me too much, maybes she knows I'm getting rid of her soon?

Any other solutions?

Thanks again!

Gav

[gRoberts]

Meh, look what I found, the oil theory seems obvious now: http://en.wikipedia.org/wiki/Diesel_engine_runaway

[maglite1]

i had an engine do this just before christmas , i had an astra cdti and the turbo bearing went awol on motorway and as i was comming off on a junction the engine just revved itself crazy as it was explained to me the turbo bearings run in oil to keep them cool and when they break down the oil gets fed into cylinders and the engine runs on its own oil , i had to stall engine in gear to stop it running.

[gRoberts]

Don't say things like that.

Expensive hobby to fix?

[maglite1]

if it was that it would be there constantly and car bellows out smoke .

[gRoberts]

the engine bay smells a little like burning oil but other than that it rarely happens and i don't get any smoke other than derv smoke.