Erratic Idle On R32

[money pit]

hi all,

heres the first of my queries concerning my half of a r32 gt. i say my half because apparently i own the half that don't work properly.

changed the timing belt, tensioners and h2o pump. we were lucky cause the old belt was rs and ready to give way at any moment, anyway we got it back together and fired it up. on choke everything was sounding good, no valves kissing pistons and the coolant was staying on the inside which is a bonus .

but heres the rub ;

when the car is warm and pulls up to a stop sign/ intersection etc the revs die to about 3-400 and if it doesn't stall then the revs will pick up to around 1100 for a second or two and then drop back to 600 where they should be.

now before we start pulling it apart to look at idle control valve, fuel pump solenoids, vacuum leaks and the inside of a duck's guts i was wondering if it was possible that the timing belt has jumped a tooth or we got it wrong by a tooth and this is causing the problem ie valves not opening at exactly the right time.

i was always under the impression that one tooth would mean it would run really rough all the time at best and at worst valves would be dancing on pistons but i read somewhere on the forum where a bloke had a belt 3 teeth out and it didn't kill it.

what do you reckon, could a one tooth mis-alignment be the problem?? or is it coincidence and we need to start looking elsewhere?? btw it was running good before we started messing with it.

regards G.

[Amec]

wouldnt it be easier to look at the idle control valve first before pointing the finger at the timing belt anyway?