Throttle sticking at idle

[hairyboxnoogle]

Ok, this is on my dads 92 7.3 IDI ATS 5 spd. 239k on chassis 110 on engine / IP since rebuild.

Problem: When letting off the throttle it will stick at idle. You have to push really hard, or pop the pedal a couple times to get it to work again.

Details: Will not do this until it is fully warmed up. RPM and throttle position before letting off do not seem to matter. The faster you let off the more likely it is to stick. IF it sticks and you shut the engine off it will unstick. It will not stick with the engine off, or while idling.

We have WD40'd everything you can see, advance plunger fulcrum and roller, throttle shaft. Throttle cable, cruise control cable. Everything seems to work fine both before and after WD40. There was no improvement. Visual inspection shows no flaw or malfunction in plunger roller, throttle movement or in the cables.

If anyone has had a similar issue or any insight please chime in. I hope its the cable, but i think its the pump.
BTW If i figure it out before he does i get $20

 

[icanfixall]

Next time this happens open the injection pump throttle by hand from under the hood. If it sticks remove the cable and try again. If the throttle is still sticking get a rebuilt pump time... And send me the $20.00 please....

 

[hairyboxnoogle]

haha, thats what we were trying to get it to do, but it seems to stick and unstick about 5 seconds later whether or not you pushing on or popping the throttle. Oh, and increasing the low idle screw makes the problem less likely, but still happens idling at 1k just half as much.

 

[flareside_thun]

Is it possible your throttle cable is crudded up? Pray some WD40 or silicone down the sheath in the cable and work it to get things smoothed out.

 

[hairyboxnoogle]

we did. we had it off flexing it and trying to get it to bind, never did