Rough idle at cold start-up

[biggieou]

The last two mornings I have gone to start up my dads truck while he is at work(we dont have 30 day tags on it yet) and when you start it up it idles fine, but if I put my foot on the pedal ever so lightly and press it down about 1/2inch and release, the truck starts to idle very rough. If I press on the pedal hard(not to the floor or anything), then the idle picks back up and idles smoothly. When I backed it out of the driveway today to bring it over into our other driveway backing up in reverse to where i was just barely pressing the pedal it started rough idling again, like it wanted to die. Now after a few minutes of warming up, this problem goes away. What do you all think is the cause for this?

 

[dan brooks]

My bet is on the sensor that controls the KSB solenoid, which increases the timing when the truck is cold. Mine did the exact same thing last year, and replacing the sensor corrected the problem for me.



Here is a link with the info:



https://www.turbodieselregister.com...p?t=120034&highlight=ksb+solenoid+part+number