Uneven tick over when cold

[Fat Boy Chim]

Hi, Took the beast out for a run over the weekend, started fine, however when cold the tickover was flutuating between 1000 - 2000 rpm. Fine while driving didn't stall and OK when warmed up, only really noticed it when i slowed down to junctions etc, Any ideas?

[Paulathome]

Give the stepper motor a clean and check the throttle flap is returning to fully closed when you close the throttle. Could be a bit of muck on the flap or around that area so give it a clean.
Cheers.
Paul.

[Fat Boy Chim]

Hi Paul,
Cleaned stepper valve 6 months ago, during general maintenance on engine etc, all i could clean was the outer "cone" piece, excuse my description, is there any thing more involved in cleaning (does it need stripping down? etc) all i did was wiped over the part that enters the engine with Meths, or does it need more than that?

[ekim]

I also have the same problem but mine ticks over at about 400-600 and almosts stalls, it s fine when warm. checked and cleaned stepper last week but no change

[philr]

It might be the cold start temp sensor. Its on the engine block near the distributor.
I don't mean the temp sensor below the swirl pot.

When mine was faulty it was a bugger to start in cold weather and if I started it and turned it off while i closed the garage door, the chance were that I couln't get it to start again or a while.
I didn't suspect this at first because I'd replaced it a few months back. Mind you I had struggled to find a perfect match for the part as Lucus don't exist anymore.

Austec confirmed it though as the readings were bouncing between -2 and 30 degrees all the time ! They replaced it for a good one and no more problems in cold weather.