adjusting the 99 DiscoI idle

[ghostrider747]

How do you adjust the idle on a 99 Disco I. I cleaned the intake and put in new plugs and now its idle is 2K. I have the battery unhooked for now while I do some radio work. It started to idle high when I went to town. When I came out of the store and started it up it went to 2K on a automatic putting it into reverse at 2K is not a cool thing.

[EdReinatAZ]

Hi ghostrider! It looks like your idle control valve is faulty. The price for the genuine part is about $200, but some people have posted replacement alternatives for the Range Rover classic with the 4.0 engine. I have the same problem in my Disco I '99, and I recently bought part CRB 21856 from NAPA for $52 and it looks like is a direct replacement. I will have to update on the performance yet. Hope this helps!

[bartell]

Originally Posted by ghostrider747

How do you adjust the idle on a 99 Disco I. I cleaned the intake and put in new plugs and now its idle is 2K. I have the battery unhooked for now while I do some radio work. It started to idle high when I went to town. When I came out of the store and started it up it went to 2K on a automatic putting it into reverse at 2K is not a cool thing.

There is no difficulty in resetting your idle, but it is best to clean your stepper motor (IAVC) first. They get very dirty and can make your idle vary. It is the most common idle issue.

Remove the device, and clean it carefully with alcohol or a spray can of carb cleaner or Quickstart (aka ether).

James

[ArmyRover]

Originally Posted by EdReinatAZ

Hi ghostrider! but some people have posted replacement alternatives for the Range Rover classic with the 4.0 engine.

Just for the record 3.9 and 4.2 were the only motors offered in a Range Rover Classic.

Basically the interchange part is a 4.3 astro van part IIRC

[dynomite]

i have a 99 disco 1 and had the same problem. maybe not the same cause but mine idled high in P/N and dropped some in D/R. thought it may be the stepper motor but it ended up being the throttle blade was letting a little air in because it wouldn't close tight. you can check that by taking off the plenum and disconnecting the air intake. pour water in the plenum and see if any water leaks through. if not, it's fine.
so i have a stepper motor from a 99 disco 1 that i bought that i could sell to you for $75 (that includes shipping) if cleaning yours doesn't work. let me know.

[lorolytle]

how did you re adjust the blade

[dynomite]

i just got a new plenum with the throttle blade in it. cost me about $100.

[1hank1]

Adjusting the idle is really hard to do......You have to turn the adjustment knob on the throttle cable.

If you were fucking around "cleaning" stuff on the plenum, then it's hard to tell what you've done. But, high idle is common on the Disco's - it's merely a ECU glitch. 99 times out of 100, it will cure its self with a few restarts.

Sometimes the stepper motors get carbon build up or black shit crammed in them, as mentioned. You can clean them, but be sure to put it back in the same way it came out...

Or, you can reset the ECU with Rovercomm.

For shits and giggles, disconnect the MAF while the engine is running and see what happens. The idle will either lower, or there will be no change.

[1hank1]

Originally Posted by dynomite

i just got a new plenum with the throttle blade in it. cost me about $100.

LOL, so the "blade" wore out?

Haha

Dude, if the "blade" was not returning to a closed position, it's because the return spring came loose or broke. Worse case, it was a $0.50 fix.

[1hank1]

pour water in the plenum and see if any water leaks through. if not, it's fine

HOLY SHIT!! Are you fucking kidding me???