Technical idel speed fluctations

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Technical idel speed fluctations

Cal2412

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Jan 7, 2020
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had a issue this morning after setting off drove short way to main road and stopped to get out and the idel speed was changing between 800 and 1000 ish while sat there out of gear engine was still quite cold but warm enough that it had dropped from "warm up speed"


any idea what the issue was?
 
any ideas its done this again today really annoying
sound like its running perfectly fine just like somebody is reving it a small ammount?
 
Hi Cal

To help you get a bit of useful help it would be helpful to advise what age and engine/fuel type you have. the mileage and some history of the care the car has had will be useful too.

Tim
 
I think its normal for engines to do that when it's cold.

It doesn't affect when driving from cold, is it?
normal? since when is normal for the idel speed to alter around 100rmp every 2-3 secsonds its never done that until reacently and never haerd of any other car doing it
 
I had same issue. Dealer just replaced sparkplugs and its gone.
 
sholdnt be spark plugs fitted irridum plugs and they have only done 3k or so

I suppose spark plugs are the only one that were changed recently? It could be that they behaved a bit differently when cold? Brand name?

Not all spark plugs are same but someone with more knowledge can help you.

Idle normally goes up to around 1000 rpms or so, when starting cold regardless of which car.

By the way, it can be a concern if it is idling roughly.
 
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I suppose spark plugs are the only one that were changed recently? It could be that they behaved a bit differently when cold? Brand name?

Not all spark plugs are same but someone with more knowledge can help you.

Idle normally goes up to around 1000 rpms or so, when starting cold regardless of which car.

By the way, it can be a concern if it is idling roughly.
ngk 6046- DCPR7EIX plugs were fitted

and im not talking about the increased speed at warm up
the idel speed it contstantly changing eg 900 one sceond then up to 1000 then back to 900 a sec later allmost like the throttle is being pressed a small ammount
 
it looked fairly clean but given it clean through with carb cleaner and a wipe out at reach what i could get to
 
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