XR8 idle

irdonn · 14-02-2010, 11:53 PM

Have a 2001 XR8 Auto.

Running like a dream until after disconnecting the battery to replace a steering wheel.

Now she starts fine but idles like a pig in park and neutral. Hunts around 300-600. As soon as she's placed in drive or reverse she picks up to 800 and all is good. Often after a drive when placing her in park or neutral she will just drop and stall. Air con on or off doesn't appear to make a difference.

Any ideas other than plugs/leads/coilpacks? I've reset the ECU using the procedure twice now to no effect.

Cheers,

Ian

Mr Hardware · 15-02-2010, 12:28 AM

Give it a week

Windsor220 · 15-02-2010, 12:49 AM

When I bought my car it idled like a dream. Then the exhaust place disconnected the battery for some reason and since then it has never been the same. Ive disconnected the battery for various reasons and always tried the resetting procedure. Works for a while then just gets worse with time.
I gave up and just let it idle like a pig.

macman · 15-02-2010, 01:02 AM

Mine was the same after the battery was disconnected. Idled way too low and would stall in neutral.

Replaced coil packs, replaced plugs and leads and replaced oxygen sensors. Made no difference...

Disconnected the battery again, but this time followed the whole procedure - 2 mins idle in drive with a/c on, 2 mins in drive with a/c off, 2 mins in neutral with a/c then 2 mins in neutral with a/c off followed by a 10 minute drive under varying throttle/speed.

Went straight back to normal (but a little better considering the work I did in the mean time).

rexd666 · 15-02-2010, 09:31 PM

Does anyone know the reset process for a manual? No matter what I try I cannot get it to idle in gear ;-)
Mine is still trying to work out how to idle and it has been a couple of weeks since the battery was disconnected. While disconnected did the coils, plugs and leads, which fixed the miss under load. The last week it has stalled about 3 times just after starting and generally in a corner, can only assume the idle drops away and the Power steering pushes it that extra bit lower and kills it.

Ride · 15-02-2010, 09:41 PM

Quote:

Originally Posted by rexd666

Does anyone know the reset process for a manual? No matter what I try I cannot get it to idle in gear ;-)
Mine is still trying to work out how to idle and it has been a couple of weeks since the battery was disconnected. While disconnected did the coils, plugs and leads, which fixed the miss under load. The last week it has stalled about 3 times just after starting and generally in a corner, can only assume the idle drops away and the Power steering pushes it that extra bit lower and kills it.

Have you checked the sock on the fuel pump and/or the fuel filter? If its cutting out when going around a corner (if you have 1/4 tank or less) it could be starving of fuel.

Boza · 15-02-2010, 10:22 PM

having exactly the same issue with my xr8 at the moment i'm gonna give the ecu reset procedure a go and take itfrom there

p.s. i already did the plugs/leads on mine if the ecu reset doesn't work then i'll suss it further. Also what is a new coil pack worth.

irdonn · 15-02-2010, 11:36 PM

Seems to be a common issue..

I've followed the full reset procedure twice now. It's been about a month and no change. It's driveable... just no longer put her in neutral at the lights.

Still fun to drive a pig though!

bodes-sh · 16-02-2010, 12:06 AM

try cleaning out the idle speed controller too, it may have crap built up in it and by resetting it back to it's default position it may be getting stuck. rip it off and clean it out with carby or brake cleaner, then give the ecu reset a go again.

irdonn · 16-02-2010, 01:43 AM

That was the plan for this weekend mate. I'll let those interested know if it makes any difference.

Cheers.

cougermoon · 16-02-2010, 11:24 AM

yeah im interested to hear if it changes after a clean. seen this happen a few time with a mates car, but normally after a reset in a week or so it go back to normal.

let us know how it goes after a clean and a drive etc

Boza · 19-02-2010, 02:19 PM

Quote:

Originally Posted by PANUP

That was the plan for this weekend mate. I'll let those interested know if it makes any difference.

Cheers.

my plans exactly

RG · 19-02-2010, 03:03 PM

I wonder how many auto AU XR8's don't do this?

Boza · 19-02-2010, 07:41 PM

i have 2 bf e-gas wagons that i use for my bussiness and when the auto plays up on them it affects the engine idle this has been confirmed by my mechanic so i wonder if the au might have a similar issue

irdonn · 22-02-2010, 02:34 PM

For those interested I had success over the weekend.

Don't know exactly what fixed the idle issue but this is what we did.

1. Disconnected negative terminal.
2. Removed the idle motor which did have some gunk in it and cleaned and bathed it in carby cleaner.
3. Cleaned all senders/plugs.
4. Wiped the throttle body plate clean which was relatively carbon free.
5. Set the base idle to approx. 600 with battery reconnected and idle motor disconnected. This was 800 previously.
6. Reconnected battery and idle motor and went through the ECU relearn process and all is good. Now idles smoothly at approximately 800. Doesn't fluctuate or stall as it has previously.

Cheers.

shazaam · 22-02-2010, 02:46 PM

Quote:

Originally Posted by RG

I wonder how many auto AU XR8's don't do this?

+1

never had a prob with mine, it's been reset heaps.

EV1LXR8 · 23-02-2010, 07:40 PM

hey i have this problem but it happened after my car backfired, mines on gas b2 converter its fine when driving but ******** at idle, where do i find this idle motor and will gas be different?

irdonn · 24-02-2010, 12:47 PM

The idle motor sits behind the throttle body. You might as well take it off and give it a clean.

burnz · 24-02-2010, 01:24 PM

de coke the IAC valve with carby clean.