Thread: Rough idling Disco

Try some Injector cleaner.
This happens also when the car has not had an "Italian Tune Up"
So give it an Italian Tune Up.
Regards Philip A

I'd also check to see if the airflow meter plug is on properly. When mine (3.5 V8i '93), came loose it did the same thing.

Pete'

Must be the time of the year...

seems a number of us are suffering this problem...

I haven't nailed it yet...

whats an 'italian tune up', Phil?

...drive it backwards flat out?

or have a bottle of chianti and forget about it.....

GQ

Almost got it.
Give it a hard drive on the highway for a couple of hours..
IMHO all 3.9s have idle instabilty, particularly with aircon on. I think its the old Hosepipe injectors, particularly when they are old and worn.
Mine has a much better idle with Bosch 4 holes.
BUT probably a combination of old plugs, old dizzy cap, old leads , old rotor,old injectors, old MAF.
First thing to do is give it an Italian, then change plugs, leads , dizzy cap, and rotor.
Depends how bad it is.
Regards philip A

Try this.

Remove the MAF multiplug & give the male flat pins a slight twist with some pointy nose pliers.

Apply some contact cleaner to the pins & female sockets & move the rubber boot back & ensure all wires are intact.

Replace & support the plug.

I chased this problem for yonks until I stumbled upon it one day, after it was running like a soleless Nike boot.

Fixed it, & it has never looked back since.

Worth a try.

Originally Posted by Shanoss

Hey guys, the Disco that i bought a couple of weeks ago is giving a small problem. Its a 3.9V8 and it aint idling right. It will Idle fine for awhile then the revs will drop right off and get very rough. It hasnt stalled yet, but it feels like it aint too far off. The motor runs fine when travelling, but like i say the idle is a bit of a problem. Throttle body was cleaned when i had a service done a couple of weeks ago as well as an idle reset. Any ideas?

Thanks

Shane

Checkout the Idle Air Control Valve on the back of the plenum chamber, I have checked 3 lately and the allen bolts were only hand tight on all 3, I had a similar problem, removed the stepper motor and valve cleaned and refitted, also remove the MAF plug, spray it with contact cleaner and the pins in the MAF and refit and make sure it is secure, some carby or MAF cleaner fluid squirted in the air hole in the top left hand corner of the MAF may help, Regards Frank.

Originally Posted by 4bee

Try this.

Remove the MAF multiplug & give the male flat pins a slight twist with some pointy nose pliers.

Apply some contact cleaner to the pins & female sockets & move the rubber boot back & ensure all wires are intact.

Replace & support the plug.

I chased this problem for yonks until I stumbled upon it one day, after it was running like a soleless Nike boot.

Fixed it, & it has never looked back since.

Worth a try.

Dido that !

i bet its the airflow meter

was on ours, was doing exactly the same thing as what you are describing, the airflow meter had had it and the car was running seriously rich