I have a 2002 f250, 7.3l, and I have an issue that I cannot figure out. Intermittently, while accelerating from a stop, or up a long grade, especially when towing my 5th wheel, the truck will stop accelerating. Usually it only happens for a few seconds and when I let off the throttle and step on it again, it returns to normal. However, unless I fully release the throttle I can press it down completely and it does nothing. The engine is still running at idle, but the pedal does nothing until fully released and pressed again. Any ideas? My son thinks it may be the throttle position sensor, but it doesn't seem to have any other symptoms. Occasionally when this happens the check engine light will come on for a moment and it will not work again until it goes off(usually only 10 to 15 seconds) Any help I can get is much appreciated.

 

It does sound like a possible TPS issue, do you have the adjustable pedals? If so the TPS comes as part of the entire pedal assembly. Also check this out: https://docs.google.com/viewer?a=v&p...M2Q5YjdmODQ4NQ
Even though it says the fuse blows, I have heard of people having intermittent issues without blowing the fuse.

 

I dunno guys, let me offer a less obvious veiwpoint; is there a chance this could actually be a defuel? Since it happens on a WOT run uphill towing with the SES light for a few seconds?

Do you know your boost #s and RPM at the point this happens? You don't have any info or mods listed on your brand new profile, and a red line mod or 38R could easily put your boost into this territory.

Rather have you rule out a defuel first than to replace a good TPS

 

IIRC if it's the TPS then the cruise control should still work as it does not involve TPS. Next time it happens while your rolling engage cruise and see if you can accelerate using that. It would help confirm a bad TPS. Need to be going approx 25mph for cruise to work so this trick won't help when it happens to you from a full stop.

 

In addition to the above, grab a can of contact cleaner and snuggle up under the pedals. Locate the sensors for the accelerator pedal (and everything else) and give it a solid shot of the contact cleaner. Let it dry before operating the truck. Maybe the potentiometers are just dirty.

 

Defuel occurs if you exceed 22 PSI boost at 2800 RPM. Do you have turbo modifications?

 

I would start by scanning it and seeing what the fault code is.

 

Unless it was modified prior to me buying it, I have no knowledge of any mods.

 

I have no known mods.

 

I have run a scan and it comes up with no codes.

 

Thinking back on this, As far as I can remember it has never happened when the cruise control is on, but then again, I do not use the cruise when towing.