Turbo Diesel Registry
Issue link: http://read.uberflip.com/i/1504224
36 36 www.turbodieselregister.com www.turbodieselregister.com TDR 121 TDR 121 SURGING CRUISE I have a 2500 Turbo Diesel, automatic with Banks Power Pack. My truck surges and backs off when the cruise control is in use: EGT changes only a little bit, but the boost varies between 5-12psi while attempting to maintain the selected speed. Hills seem to be a factor. Sometimes the truck maintains the speed with no surges or back-offs, and when I don't use the cruise, it seems normal. Jake The Snake Lower the power setting when using cruise control. The cruise was calibrated for standard output, but now power comes aggressively, and it overshoots target speed, backs off the throttle, drops speed, then repeats the process. Killer223, mpaulson LIFT PUMP REPLACEMENT On the driver side of the engine bay there is a ticking sound when it idles. Using a stethoscope I can isolate where the sound is coming from, and I think it may be due to a weak return spring for the lift pump plunger allowing the rod to lose contact with the cam. I already have a replacement that was purchased from Geno's a while back to carry as a spare. Any thoughts from the audience on the noise? Iron Duke II How long has it been since you changed your fuel filter? My '95 would start tapping a bit when I was getting close to a filter change. For a simple test, while it's running, take a pair of pliers covered with hose or something smooth that won't damage the hose, and squeeze one of the rubber hoses on the filter side of the lift pump and see if the tapping changes. You don't want to clamp it off with a Vise-Grip, just squeeze it together and release it. If the tapping changes, you could try replacing the lift pump. BigPapa I changed the lift pump and the ticking noise has ceased. I also ran across a video which mentions using a Comp Cams 973-1 valve spring in the lift pump for higher-rpm, higher-power applications. I just left mine as new. Iron Duke II WON'T GO WOT I have a new-to-me 1998, 12-valve with automatic transmission. I am having issues with the throttle linkage. On my scanner, the TPS is reading 59% at wide open throttle and about 6.7% at idle. I took the sensor off and, with a screwdriver, verified the TPS is showing 99% at WOT, but when I have everything put together it's at 59%. It's not hitting the stop. I measured the ball stud to the bracket and it's right at five inches. What do I need to do? Do I need to adjust the linkage rod or something else? Austin1985! What condition are the bushings in the linkage? If they are worn, the lever will go sideways instead of fore and aft. GAmes Try the simple things first: Does the foot pedal go all the way down or is there a floor mat in the way impeding full travel? How about the correct position of the cable housing in all brackets? brucejohnson On closer inspection I found out that my "high idle stop screw" is out too far, only allowing the TPS to be at 59% at WOT. I'm not sure how to turn the screw in a few turns to get more travel because it looks like the head of the screw is round from factory. My only guess is the screw must have backed out after so many years. Austin1985! The high idle screw should have had a security wire in it and, if I'm not mistaken, there's a round cap on the screw to prevent tampering. If the wire is gone, the previous owner has been messing with it. I'm sure there's a procedure to adjust it, but all the service manual says is that you should not mess with it. BigPapa Thank you. I actually got it out and put another screw in. Just took some pliers and moved it back and forth. It came right out. I didn't see a cap on it. Everything is perfect now. I do appreciate your help! Austin1985! BRAKE CHECK VALVE My truck has a bad power brake check valve (Mopar 4746381). Does anyone know the specs of this and/or what is a compatible substitute? Raymond Wiedower Rockauto has them, Dorman 80189 or 80190, less than $5. BigPapa Coverage of the '94 to '02 Model Trucks. Website Correspondence Edited by G.R. Whale.