94 auto ctd high idle issue
 

i have a buddy who has a 94 ctd that recently decided to rev up to 2000 rpm when not in gear. if its in gear it is just below 1000 rpm while you're stopped. When driving on the highway it'll cruise at 60 without the pedal being pressed like cruise control. Now he hasnt messed with the pump he says but the guy he got it off of did. the throttle linkage isnt broke and the springs are there he said. I havent seen it yet. Any ideas? Hes now offering it to me for my old ford gasser and im really considering it.

So you're saying that since he revved it up in neutral, his truck idles higher than it used to? The first thing I would suspect is that the ball sockets on the throttle rod are sticky or seizing up. The early throttle cables also had a problem with fraying and sticking. There was a recall that covered both issues. It may not have been done, or the recall parts might be wearing out.

When it's sitting there idling high, open the hood and grab the throttle lever on the injection pump and manually push it down onto the low idle stop. If something was holding it off the idle stop, you should be able to trace the linkage toward the cable to determine what is binding. If it already was on the stop, you know the problem is further downstream and into the pump.

Pop the linkage off the throttle lever on the back of the pump. Then it isolates it from any linkage/cable issue. If it still revs high, drop the idle screw down. If it won't idle after that, then you have other issues. Since it drove fine for so long, there could be damage inside. But if you back off the gov springs about two clicks and reset the idle. Typically if the gov springs are too tight, and you won't be able to get the idle to a reasonable level without it dying.

ok thanks. I wont see the truck till saturday. he just told me a diesel mechanic where he lives said he needs a new governor in the pump. He quoted $300 for it. Does that sound right?

$300 sounds way high if the problem is just the cable or linkage.
I'd eliminate those for a cause first.