high idle on second start when warm

[Basil]

Hello All,
I have 96 disco. Recently it developed a problem-imagine that-
Anyway when I first start it it runs fine starts fine. Then once it's warm, and I shut it down, I come out restart it. It starts fine but the idle jumps way up at 1600 rpm and stays there. Blipping the throttle doesn't help. Shutting it down and restarting just does the same thing. The engine check light has been on even before this problem. I've check the codes and they indicate fuel metering fualt, electical fualt, Oxygen sensor fualt.
The car always starts fine and when it's the first start of the day it idles normal There is no black smoke. I thought it was a dirty stepper motor so, I pulled that and it was very dirty so i cleaned it and the oriface where it goes with brake clean. I started it it ran great. I got it hot then shut it doen. It started right up but now the idle is at 1800rpm! Should I just replace the stepper motor?

Note; when i went to get an inspection sticker last july in Massachusetts, the engine light came on so I checked the code and it gave fuel metering codes and OXegen sensor front right bank. So i switched the front Ox sensors from left to right and I switched them in the harness to see if the code would follow it. I then cleared the codes. Then the light did not come on so for a week so I just got my sticker. Then after a week or so the check engine light came back on. It's been on, I've turned it off after finding fualt codes that show fuel metering Oxegen sensor, electrical fualt. Then in the past month this high idle problem showed up. But I doubt this high idle problem is an Oxegen sensor. All I care about is getting this beast to idle normally. Who cares if the light is on; it's pretty anyway..... Man, I love my 1967 series 2A!!!!!!!!!

[Hammer38]

You might need to set your base idle. You need to clear the fault codes, reset adaptions and then set your steps between 20-30. The engine needs to be warm and you should clean your throttle body also. You'll need access to a T4, so you might need to take it to a shop. We normally would charge one hour for this repair. Without having your car in the shop, this is my best guess.

As far as the fuelling & elec. faults for your O2 sensors:check for any water ingress in the sensor connector. I've seen a few O2 faults caused by this on bank 2 (right side). O2's for DI's are expensive, so try cleaning the connector with a good elec. contact cleaner. If some pins are corroded, you can usually find pre determined leads to replace them. Hope that helps.

[Basil]

Hello there,
Thanks for your response. I had already brought it to my mechanic before I got your response. I gave up. He found that the stepper moter had burned itself out due to a what he suspects may be a bad main ECU. He pulled the ECU and then put it back it in. Now instead of a high idle the truck won't hold an idle at all. He is waiting to get used ECU to test that. If indeed that's what it is he'll put that one in. He also mentioned he has the top of of the line Land Rover diagnostic equipment and that it could not read my car, but that a cheapo tester that I had in the glove box could at least get the codes and reset the computer. I'm not used to all of this electronic mumbo jumbo being a series truck owner. But my wife loves the Disco.