Starting to get really frustrated with this. I waited and waited and finally found the truck I wanted- 2002 F350 CC LB Dually 4x4. It wasnt mint by any means but I have been gradually taking care of all the things it does need. One problem I haven't bren able to sort out is an annoying low speed throttle drop. I have read lots and lots of surging/bucking/ no throttle response posts but no conclusive solution yet, and they all seem to be a bit diff than my issue....
when I am going slow and have just light throttle application, and I hold the pedal at that position, the engine will idle back down, then come back, drop to idle, rinse, repeat. I thought TPS and got the new pedal assembly with IVS and TPS (combined unit) but it still does the same thing at the same spot. Could be a faulty TPS in the new pedal assembly but really...the exact same throttle position??? I am assuming the new pedal is good. So what else happens just off idle?
The IVS opens- it must be working fine because the throttle does work initially, right? Highly unlikely the IVS would open initially and then reclose?
could a dieing IDM cause these symptoms?

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I think I would give it, the TPS, a can of electric parts cleaner first . Give it a squirt the work the pedal some then another squirt rinse and repeat. Some times potentiometers collect dirt and wont make contact in certain spots. It worked on an old ranger and my expedition a few years back and on the wacky radio dial on my f250

 

 

Hi Fuzzy Dog, That the same problem I have with my 99, 7.3 I fought this for the past 3 months, bought a new ford Pot for pedal from ford. Not hard to change, I remove the 3 bolts holding the pedal. Installed new one. Remounted, Started engine. NO response period. Like I'd blown a fuse or
didn't plug back in. Which I did. Recheck on contact, still nothing. Has me stumped. Hope I see where you fixed the problem. Rusty