4.8 rough idle only when cold

[Jimmycrackcorn]

I was wondering if anyone has had some experience with an erratic idle to the the point of stalling at times only on cold starts.After 20 secs or so it is back to normal and and no probs till next cold start.2002 gu3 4.8 ti 150k on clock petrol only.cheers..

[Alitis007]

Usually its related to a coolant temp censor but they can be a bit expensive but what you can do is clean your AFM but be carefull not to wreck the little filament in it and also clean the idle speed motor and lubricate it try not to break the gasket. You can use carby cleaner and crc / wd40 to lub. Cheers

[Jimmycrackcorn]

Have checked resistance of temp sensor in different temp water seems to be operating within specs..got quoted 92 dollars for temp sensor ,happy to replace the original if i could fault it.
I will check your suggestions and see how I go.thanks for your input.

[Alitis007]

Might awsell do a static tune aswell like air & fuel filters and spark plugs if ther not platnum i change mine every 10k regardless of condition and clean the throttle body, i always say you only get out what you put in! Also check the resistance of the leads and check the condition of the rotor button and cap while you there it might not have anything to do with the fault but atleast you might be able to eliminate those simple things aswell.

[Xtreme 4x4 Sport]

Might awsell do a static tune aswell like air & fuel filters and spark plugs if ther not platnum i change mine every 10k regardless of condition and clean the throttle body, i always say you only get out what you put in! Also check the resistance of the leads and check the condition of the rotor button and cap while you there it might not have anything to do with the fault but atleast you might be able to eliminate those simple things aswell.

What leads & what rotor button and cap? It is a 4.8 and has none of that.

Cheers
David

[Alitis007]

What leads & what rotor button and cap? It is a 4.8 and has none of that.

Cheers
David

Sorry mate was thinking of my 4.5 haha if its got coil packs with an ohm meter check the resistance of the primary and secondary circuits

[Xtreme 4x4 Sport]

Sorry mate was thinking of my 4.5 haha if its got coil packs with an ohm meter check the resistance of the primary and secondary circuits

I knew you meant that