Hi Everyone Funny this one - I occasionally get what appears to be a bit of a sticking throttle or slow revs to fall back to idle. I've cleaned the throttle body and the idle control valve fully and there is not too much tension on the throttle cable but occasionally when town driving I get the revs fall slowly and sit at about 1100 rpm for about 5 or 6 seconds then it will fall to the regular 850-900 rpm. Anyone got any ideas? Boost pressure is spot-on and doesn't falter etc. I'm going to take the TB off again tomorrow to inspect and make sure nothing has got sticky etc, and also double check all the hose connections etc.. Will

it seams to be an unexplained gremlin of the cars i have 3 850's 1 t5 and they all do it and we are not the only ones

good - that's reassuring! I'll give it a once-over tomorrow and probably reset the ecu again too, just to try it.

Make sure the idle air valve shutter is 'floppy'. if it's sticking at any point it will cause the symptoms you're experiencing.

Sorry to jump onto your post itguy but i have a similar problem. It idles about 950 at best, sometime 1000 or a little higher. Today it dropped to 850 which is where its meant to be for a few seconds then back to 950! If i very shaply dab the throttle when its at over 1000 it'll drop to 950. Ive cleaned the throttle which was dirty so now its all clean and free and the idle air valve is clean with the floppy bit floppy! Its very annoying.

thats a different problem that sounds more like adjustment needed on the throttle cable or poss even sticking

Another possibility is that there is a small induction air leak. Look particularly at the rubber elbow at the left end of the inlet manifold.

thigs i have tried on the t5 to counter this problem :- iac valve, idle control valve, inlet cleaned, pcv system completly replaced, all air hoses and vac hoses replaced, fuel rail replaced, fuel filter replaced, full stage 0 tune, i also have brand new turbo hoses and elbos. I have not tried to rectify the problem on the other cars as it's no a big issue and i dont have the money.

i checked the little elbow on the left-feels ok. might remove the inlet manifold, clean out the throttle best i can then refit with new gaskets. the throttle cable if fine, and has some slack.