Sudden sticky throttle

Hi,

This morning my ST220 started continuing to apply power when I lift off the accelerator (resulting in 6k rpm during gear changes). There is no slack in the accelerator cable and the cruise control cable isn't pulling on it.

I connected it to my computer and found that according to the TPS the throttle remains open after releasing the pedal, sometimes sticking at the previous point and sometimes dropping to 20% (closed is 15%). I've whipped the air filter housing off and can't see anything wrong with the throttle itself and it does appear to never fully close unless I force the bracket the cable attaches to back to the closed position.

It was fine the previous drive but yesterday I did remove the battery and air filter to do something else and might have disturbed the cable a bit but nothing major (I didn't lean on it or anything) :)

Obviously this all points squarely at the cable getting stuck in it's tube but is it usual for this sort of problem to come on this suddenly?

Cheers,

Peter.

Reply to
Peter Spikings
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Yes, but it's also a symtom of the engine earth lead falling off & earthing back via, thus overheating, the throttle cable.

Reply to
Duncan Wood

Yes, I suppose that'd be bad ;) I'll double check that but I vaguely remember checking the earth straps and connections when I had the battery out and they seemed fine.

Thanks,

Peter.

Reply to
Peter Spikings

TPS at fault I would say.

What does scanner show KOEO ?

Tim..

Reply to
Tim

On 23/06/14 16:34, Tim

It varies, depending on the position of the throttle :) I'm not trying to be sarcastic, it looks like it isn't the TPS.

It's most likely resting place is 20% (15% is fully closed IIRC) but if I press the accelerator until it says 50% then let go sometimes it drops down to 20% again and sometimes it sticks and the pedal stays down, which mirrors what looks like is happening at the other end of the cable. If I manipulate the throttle directly it also seems to read a sensible value.

Need car for work and kids playing up a bit so the AA are on the way :)

Thanks,

Peter.

Reply to
Peter Spikings

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