damb blue temp sensor.....aaaahhh

[theclash]

usual story car would rev on its own when cold so bought a new blue temp sensor from vw fitted it and its just the same if not worse, isv is spotless and there are no broken wires. next step is to replace vac pipes although they all seem fine and no leaks idles spot on when warm but really pi##ing me off randomly reving when cold especially sat at traffic lights and the herbert at the side of me  thinks i wanna race. any more ideas that i can try . car runs spot on otherwise its a 92 8valve

[squires]

i had the same problem, my inlet manifold was lose only 2 studs were holding it on, nice lambretta by the way

[theclash]

dont think mines loose but it it is annoying......

[Alec]

I was gonna suggest maybe an air leak in the manifold. Heard a few people mention the idle valve, maybe a loose connection on that? have a play around with that whilst its doing the crazy revs and see if it stops it

[weazgti]

Mine done this when i bought it,kept trying to clean it and eventually got a mk3 one while walking round the scrappy and cleaned that instead.
Had to adjust the idle up cos if it was too low it done it slightly.

[theclash]

love my car but this little niggle bugs me. after doin a search (yea i know i should have done that in the first place) it seems a common problem and can be hit or miss as to what it is  

[rubjonny]

check the idle switch, needs to click with throttle shut. make sure cable not too tight, should shut firmly against the stop. check the wires to the back of the throttle body, prone to snapping back there.

[Bcarm]

S :sad:orry to jump in but i have the opposite problem runs great when cold but as soon as it warms up starts to miss an pop etc.

[Alec]

When mine did that it was just after filling up with petrol at morrisons, I thought it was the petrol but turned out to be dizzy cap and rotor mate. Might not be the case with yours, might be worth having a look inside for any evidence of damage though

[Bcarm]

Thanks for that, was going to change the lot shortly (plugs, leads, cond, rotor, dizzy cap etc you get the picture)
What does the blue temperature sensor do? :embarassed: