Yesterday, the normally hour and ten minute drive home took me 2 1/2 hours because of a recurring but intermittant and really annoying problem.

This only is an issue on cool and damp days, and when the truck is cold - sitting 8+ hours. The truck starts and idles fine. When I start out, it seems sluggish and somewhat unresponsive but it does accelerate to speed okay.

After awhile, I get zero throttle response and the SES light comes on. Absolutely nothing happens when I hit the pedal. I can stop and let out the clutch (ZF6) and I can sometimes get a little throttle and the light goes out, but it dies out at about 1500 rpm and the light pops on again.

It seems like once the truck is warmed up and running for awhile - like an hour, the problem magically goes away.

Last spring I had this problem and the dealer replaced the Pedal Position Sensor.

My best guess is that moisture is messing with something, but I have no idea where to start. I did attempt to trace the pedal wires from the sensor, but they run up into a big loom in the dash.

The dealer said (correctly) that it would be nearly impossible to diagnose unless it does it when they have the vehicle.

Anyone have any ideas?

 

That is correct, They'll have to be able to duplicate the problem to correctly diagnose it. I have seen repeat pedal failures on these trucks so don't rule out the pedal assembly yet. I've also seen devices that are tied into the throttle pedal cause this condition to occur.

 

You'd think the dealer would have a device that could be hooked up to record that problem more precisely since it is obvious they get no indication when checking the chip history? Be a great little invention for some one??? Check it out at your local dealer, drive till you expereince the problem then bring it in for analysis...

 

If they can't duplicate it, ask to have the VDR hooked up (vehicle data recorder). The VDR basically will take a snapshot of the system for 30 seconds prior to and 30 seconds after you hit the button. When the truck acts up, you just hit the button on the VDR and it records the data of what is happening so that the tech can analyze it later. Very helpful tool.

 

I had the same exact problem and took 1 year to finally diagnose it. The problem was in a wireing harness that is connected to the gas peddle. The dealer found the problem on accident on a cool damp morning (which can be rare in e. washington). They found a frayed wire. Tell the dealer to mess with the wires while it is running and see if it causes no response. I went through 4 peddles before they fixed it. I told them to look at wires the 2nd time around, but no they follow that stupid manual and won't do anything to figure out alternative causes. Hope this helps. oh and by the way, I have the same exact setup your truck has. 2002 F-250 SC 4x4, 6sp, psd, manual transfer.

 

Thanks for the heads-up Colt, I'll take that harness off and give it a good look-see.

Our rigs are set up almost the same - I have ESOF. Chicks dig the ZF!

 

Hey Oppy,

Be sure to look carefully, appearantly it was hard for them to spot as well. Their solution I am told was to tape the exposed wire and make sure there was good contact.

 

It seems to me that if the SES light goes on there "should" be a code stored, I could be wrong though.

 

I woulda thought that also, but there's nothing stored. I did have my Predator plugged into it once and it was giving a throttle position sensor error, but once the truck started to run okay there were no stored codes.

I'll take a really close look at that plug Colt - thanks again.

Can anyone recommend a good aerosol wiring dryer/protector?