When it's in any gear it's fine, but in park it idles at like 3000rpm... I pulled the throttle cord a few times and still idles at 3000, what can I do?

 

Ok starting to get my hands dirty to no remedy, anyone have info?

What i've done so far...

Drilled out the aluminum saftey plug on the idle hex nut, backed that down to min idle, nothing
replaced a broken vac line, nothing

I see there is a hex stopper for the throttle arm on the TB, haven't tried to back that down, wonder if that'll work...

Also when I make a change, plug the batt back in, it'll start, but on the next start it just turns over and over, nothing... I have to pull the batt, plug it back in, then drive around for a min in order to have it start back to back.

 

Ok, so I found remedy without the help of you guys... Are there any techs in here or are answers just slow because it's the 4th? haha..

Anyway here is the issue, I spent more time following around vacuum lines and cleaning sensors than spending time focusing on the obvious.

I simply greased the throttle arm and lowered the TB bump stop to its min which it was very close to min already, that provided a drop in rpm to the tune of maybe 200 rpm, so it was idling between 1200-2500.

I noticed several stress fractures in the aluminum head that makes contact with the TB bump stop, it was bent to a 45 degree angle down which provided more throttle. I couldn't pull anymore rpm because it was bent so far down. It looks like the previous owner or some shop that had it at some point tried to step the idle up by just bending the thing, perhaps after the the real issue was fixed, maybe a computer reset or something, and this high idle condition lingered. Anyway I took a tortch to the aluminim where it was stress cracked, bent it back strait, then fired up the disco again... RPM would go to 1000 then drop to 400 then hang around until you got in gear, followed by a stall. I moved the hex bump stop up 2 threads and it's right at 750 idle.

Thanks for all the help, haha.

 

You need to reset everything thing back the way you found it, remove the air intake hose and clean the inside of the throttle bosy tube and butterfly of all carbon and grease build up. Then you need to clean the spetter motor, IAC or idle control valve, what ever they were called for your years truck. Once you clean it out you should be fine.
Mike

 

I did all of that and it still didn't fix it, look up a few posts as I explained my remedy... Thanks for the info though, always helpful.

 

My mates Disco had the same problem and it was the spetter motor. There is a way to bypass the the spetter motor and manually adjust the idle, if you wish I can find out how this is done.

 

Yeah that would be great if you could post that up, i'd be curious as to how it works without it, although it's running great right now except it still doesn't start all the time... Until I can trouble shoot that sometimes I'm forced to pull the battery, plug it back in and it starts. Makes me think there is a sensor on the way out or something, perhaps a fuel pump issue...

 

Had the same problem a while ago on my D1!! replaced the stepper motor,cleaned MAF,cleaned intake, and relaced the wires and plugs. Turned out it was the TPS!! A member here told me to check it!! Went to the local junk yard and it cost me $10!!

 

Sounds like it is time to see if there are any codes???
Mike

 

Ok, what you have to do apparently is remove the vaccum line off the back of the stepper motor and put a plastic bag over it to seal it off. That will bypass it aparently until you can replace the stepper motor. Hope it makes sense cause that is my mate told me he had done.