IDLE Sound?

[TONY3R]

Used my NOBLE on Friday when it was pretty warm for this time of year. Now its probably nothing but after a drive I noticed that when I got out to open the garage door the car's idle sounded different than normal. I looked at the rev counter and it was reading 800 then 850 then 800 then 850 roughly, in other words you could hear the idle going slightly up and then down etc etc.

Is this anything to worry about? Or could it be the warm weather? I had the car serviced at the NOBLE factory just 400 miles ago. Also when I got the car back from the factory the horn didn't work is this easy to fix? Has this happened to anyone else?

>>> Edited by TONY3R on Monday 21st March 15:21

[lucozade]

I had this idle noise issues yesterday at the Owners day meet. Vengatune told me my engine was "hunting" and might be in need of a ECU update.

It's now booked with my dealer for next week.

Apparently the idle sound should be a constant blurb rather than it sounding like its dropping and coming back - so I was told.

[m12_nathan]

It could be caused by an air leak (split pipe?) in the inlet? unmetered air could be causing problems?

[DanH]

lucozade said:

I had this idle noise issues yesterday at the Owners day meet. Vengatune told me my engine was "hunting" and might be in need of a ECU update. It's now booked with my dealer for next week. Apparently the idle sound should be a constant blurb rather than it sounding like its dropping and coming back - so I was told.

Shame you didn't chat to Roush as they were there doing ECU updates if you asked. I got mine done for no good reason, and can't tell any difference although it is a newer map

[ThatPhilBrettGuy]

Mine hunts very slightly and I believe I've the latest 3R map. Much better low down torque with this map too (which I'm sure the Roush guys' will tell you it's just as well, as they know how much weight it's got to get moving )

[joust]

Check the lamda sensor (they sometimes snap off for some unknown reason) and air leaks around the exhaust manifolds.

Both are known (and I've expierenced both) to cause what you describe.

Parts to fix both are a few £10s plus a small bit of fitting if it is that.

J