Mornin guys and galls.

This is my first post, and unfortuneatly, it is one for a problem with my 93 Favorit.

When the engine is cold it idles perfectly, then as soon as it is up to workin temperature, the idle speed increases to 2000rpm, then continually goes up to 3000rpm and then straight back down to 2000rpm again, It does this none stop while idling. The aggravating part about this is that the engine runs beatifully at all other times.

I have found that if I unplug the lamda sensor the idle speed is better but not good. I can't see, given the job that the lamda does, that it would be the cause.

Anyone any ideas before I put my left arm in a vice and saw it off in frustration please?

Regards, Barry.

The lamda could be sensing oxygen in the exhaust and fuelling accordingly, hence the fast idle. As it does it when the engine is hot (things have expanded), check for air leaks on the intake side.

Sounds like there may be a fault with the coolant temperature sensor.

wey hey!!!!! Thanks guys, will go play and see what I can find out. I'll post any outcome on here, thanks for your help.

Regards, Barry.........................BBBBBBBBBBBBBB