Cutting in and out!!

[JHud]

We just bought my father a 06 F-350 with 100k....truck is bone stock but has one issue i cannot figure out or even know where to start looking...

The truck starts perfectly and idles just fine every time....wen u go to give it throttle it comes up fine but every 3-5 seconds the truck will go down about 500-1000 rmps and come right back up, just like the trucks do when they shift gears....doesnt matter if the truck is in park or going down the road, it does it the same...i have no idea where to even start troubleshooting so any help is much appreciated...thanks guys

 

[LReiff]

Exhaust back pressure sensor...just a possibility...first I would check for codes or put it on a Diagnostic Scan Tool and watch the engine parameters while driving.

 

[JHud]

Any idea where that is located?

 

[JHud]

Found the problem, u'll never believe this....

Well the fuel gauge wasnt reading reading so we were dropping the tank to see if we could fix that problem and noticed the fuel tank guard was crushed up alittle, so we took the guard off and cranked the truck just for ****s and giggles.....and what do u know, the gauge and cutting in and out problem went away....idk what happened but we straightened the guard and put it back on and all is well now....thanks for the help though....now we just gotta make her fast!!!!!!

 

[Bobus]

The truck was goin into Limp Mode, If you get below a certain level in the tank the truck will go into "limp Mode" Greatly reduces power to help prevent damage to the engine.. My truck had the Fuel Sender take a crap and i was tryin to pull 37K lbs talk about a PITA havin no power and intermittant cutting out.