Quick checks for strange issue
 

Before I take my classic 1999 uk turbo into a garage i'd appreciate any basic checks that can be made. Car cut out at traffic lights, I was able to start it straight back up but it wanted to die again, I had to keep throttle pressed so it didn't. For the next few miles when i slowed i had to feather the throttle on idle so it didn't die until I came to a halt where the engine ticked over fine. I'd assumed it was the battery so trickle charged it over the next few days. I thought nothing of it until I took it out for a spin and it did the same thing!!!! Starts fine, tried to die when I stop but when I park up at home seems fine!!! Are there any basic things i can check before I take it in? I've since tested the battery and alternator and they are coming back ok.

Clean out the idle control valve.

interesting you should say that!! I think I just found one in the glove box, I guess it's a spare from the previous owner, I wouldn't leave a broken one in. I'll swap em out and see what happens. Cheers

Swapped them over, the one that came out didn't look too bad until I started cleaning it. Some real crud around the o ring. But the worst was inside the housing, took me a while to de coke it all. Also glad I have the model that's easy to get to, I watched a video of a guy taking all sorts of pipes off to get to it. Even if it turns out not to be this it can't have harmed giving it a good clean. I'll take it out for a run tomorrow, don't want to wake the kids, :-)

Seems to have done the trick, I put the original back in after cleaning as that spare one from the glove box caused idle to hunt about. So it's in the bin!!! Who leaves a dodgy IACV in the glove box, :-) Took it out for a spirited run and all seems fine, so Thank you.

Other one you threw out may not have been dodgy, may just have needed the ECU to get used to the other sensor and make corrections. I've heard of cars running rough or cutting out until the ECU adjusts.

My pleasure.