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Gary, Australia Car Mechanic
Category: Australia Car
Satisfied Customers: 999
Experience:  Senior Technician
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I have a 2004 Automatic Nissan X-Trail, and past few weeks

Customer Question

I have a 2004 Automatic Nissan X-Trail, and for the past few weeks it has begun revving up to 3000kms on cold starts in the morning, and takes around one minute for it to drop back down to 1000 revs.
I have made sure everything is turned off before turning on the car (aircon) to make sure its not a battery issue.
If the car isnt used for a few hours, it can rev high again, and today it was bouncing up from 1000-3000 revs as if I was pushing on the pedal, which I wasnt.
Only did it for around 30 secs, but its enough to worry me.
Can you help?
Submitted: 1 year ago.
Category: Australia Car
Expert:  Gary replied 1 year ago.

Hi Jo,

Has this only started happening since during Winter now, and how cold is it where you are?

There is a few things to look at, all regarded as part of engine servicing.

I would have the throttle body cleaned including the idle control valve IAC, and an upper cylinder clean.

I would also scan the engine for codes, and perform an IAC reset after all the cleaning procedure.

Many workshops can do this for you.

Hope this helps.


Customer: replied 1 year ago.
Hi Gary
Thanks for coming back to me. Its only really started happening the last 2-3 weeks, I live in Perth so the weather hasnt been too cold, plus its in a garage when its started, so maybe worst between 2-10 degrees.
A few people have mentioned it might be the spark plugs, an air leak, or maybe the automatic choke.
Is there any fix that doesnt require a mechanic, or would it be best to book it in now before it gets worse?Thanks
Expert:  Gary replied 1 year ago.

Hi Jo,

Your vehicle engine speed is computer controlled from the ECM.

The ambient temperature at startup in combination with the coolant temp, are the main factors to idle speed. Sometimes carbon buildup causes the idle control to overstep the mark.

EFI vehicles control there target speed with bypass air control, gives the same effect as an Automatic choke of a carburettor, but no components are similar.

Nissan is your best bet to drop it down a little.

Kmart, Ultratune are worth a go as well.

3000 is certainly too high, 2000 would be more acceptable.

I hope this helps you.

Kind regards


Expert:  Gary replied 12 months ago.

Hi Jo,

Have you had any success with your problem?

I hope my advice has been of assistance to you.

Kind regards