Idle Hunting on M12

[GTSnooze]

Has anyone experienced this on their Noble.

Im looking at a 3R and have noticed that when I pull the car up after a run, the revs are hunting from between 800 and 1300 rpm at idling.

Is this a normal Noble trait and if so is there an easy fix. Or perhaps is this indicative of something more sinister?? Don't want to end up buying a problem car...

Would welcome any feedback - Cheers guys.

Dan

[Twerlie]

It could mean that the throttle body and butterfly needs cleaning?

[AMG Merc]

Twerlie said:

It could mean that the throttle body and butterfly needs cleaning?

Only clean the throttle butterly valve if it looks grubby and/or the car is high mileage - I did mine after comments here and regret it as now my cold idle has permantly increased. Cleaning can strip away a laquer on the valve - although this presents no problems (apart from the noiser startup).

Joust mentioned a rubber air pipe somewhere that works loose amd can cause this sympton?!

[sean_goodman]

i tried all the things above and didnt solve mine.

got hold of the noble software, put in on my laptop connected up and did an idle reset, sorted the problem perfectly.

just remembered i had a pc crash not so long ago and lost the software, cant remember where i got it from now but i thing i might have been off noble parts

[sjc]

GTSnooze said:

Has anyone experienced this on their Noble.

Im looking at a 3R and have noticed that when I pull the car up after a run, the revs are hunting from between 800 and 1300 rpm at idling.

Is this a normal Noble trait and if so is there an easy fix. Or perhaps is this indicative of something more sinister?? Don't want to end up buying a problem car...

Would welcome any feedback - Cheers guys.

Dan

Wouldn't have thought it was too much to worry about, happened a couple of times on my previous 3R, and was always a quick fix at Noble London. Might be worth calling them and talking to Skippy the mechanic there, he'll be able to throw some light on it I'm sure.

[JLSELAN]

This is a pretty common problem if the base idle speed is not close enough to the 850 rpm set point. Basically, the ECU is trying to keep the idle close to the set point but the throttle position is off (high or low) due to missadjustment and the idle speed fluctuates as the ECU "looks for" the correct setting. As mentioned, adjusting the idle and using the "reset adaptive maps" on the diagnostic software should sort it out.
BTW, the permanent fix is an ECU reflash that includes a new idle strategy developed in the U.S.

[sean_goodman]

can anybody point me to where i can refind the software

ok found it now lol

Edited by sean_goodman on Sunday 6th January 19:33

[gaz 7404]

What is the correct rpm for idle?

[joust]

One other thing is that it can indicate either a lamda sensor on the way out, or more likely a leak in the manifold/turbo joints. I've had this ~3 times now.

Finally, also check your sparkplugs condition and gaps. As the idle isn't "closed" small variations can make this happen.

J

[GTSnooze]

sjc said:

GTSnooze said:

Has anyone experienced this on their Noble.

Im looking at a 3R and have noticed that when I pull the car up after a run, the revs are hunting from between 800 and 1300 rpm at idling.

Is this a normal Noble trait and if so is there an easy fix. Or perhaps is this indicative of something more sinister?? Don't want to end up buying a problem car...

Would welcome any feedback - Cheers guys.

Dan

Wouldn't have thought it was too much to worry about, happened a couple of times on my previous 3R, and was always a quick fix at Noble London. Might be worth calling them and talking to Skippy the mechanic there, he'll be able to throw some light on it I'm sure.

Thanks sjc, I'll give Skippy a call tomorrow.

[gaz 7404]

my 3R doesnt hunt but does tick over at 1000rpm is this too high?

[JLSELAN]

Forgot to mention. The reading on the car's tach is pretty un-reliable at low rpm, so it's best to get a digital read-out (like the one provided by the diagnostics software) for setting idle speed.

[Biggriff]

mail me Sean and I will give you the link

[sean_goodman]

Biggriff said:

mail me Sean and I will give you the link

cheers mate, found it again now

[T&T]

Whilst looking for mine last year , I drove a 3r with very similar symptoms. From cold to warm it was fine , but after a good thrash it would hunt. I removed the oil filler cap , and the crank was being pressurised. The dealer tried the "they all do that sir" line , whereby I lost interest immediately and went and got one elsewhere,which funnily enough didn't(do that!). It could have been a blocked breather or more serious, who knows without a full inspection.

It could be one many things , but I found the price is pretty much fixed for any of these cars , so you might as well shop around for one that's either right form the Start , or the seller will sort before you buy.

All IMHO obviously.

cheers