When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hello everyone, I have a 2003 F-350 Lariat 7.3L. I have had the truck for about 6 months now. It just recently started shutting down on me at random times while driving. I lose all power steering and all engine power. After it initially happened I found out there was a recall on the crankshaft positioning sensor and the speed control modification system. I got the truck to Ford and they replaced the recalled parts. When I left the dealership I was only able to get about 500 yds before it shut down again. I pulled it behind my other vehicle back to the dealership and its been sitting since. I have noticed that it shuts off when the transmission temperature gets to normal operating range ( the engine temp doesn't have a chance to get to operating temp before it shuts off). Could it be a transmission temp sensor? Any help would be greatly appreciated. Thank you in advance.
No, it's not the temp sensor for the transmission.
You most likely have an intermittent power feed to the PCM (main computer). Replace the PCM Power Relay and see if you get lucky, it's the most common reason for intermittent stalling like you're seeing. Since you have a diesel, there's a lot more that might do it, so be patient and work through the possibilities. If the issue goes from being intermittent to continuous, it will be a lot easier to diagnose. Intermittent faults will drive both the owner and the technician crazy.
For some reason (there is a good chance I am wrong) I am thinking this may be related to the battery connection/terminal that is on the drivers side fender well under the air box. I saw a post recently similar to this and the terminal had corroded enough so that it was making an intermittent connection.
Hello everyone, I have a 2003 F-350 Lariat 7.3L. I have had the truck for about 6 months now. It just recently started shutting down on me at random times while driving. I lose all power steering and all engine power. After it initially happened I found out there was a recall on the crankshaft positioning sensor and the speed control modification system. I got the truck to Ford and they replaced the recalled parts. When I left the dealership I was only able to get about 500 yds before it shut down again. I pulled it behind my other vehicle back to the dealership and its been sitting since. I have noticed that it shuts off when the transmission temperature gets to normal operating range ( the engine temp doesn't have a chance to get to operating temp before it shuts off). Could it be a transmission temp sensor? Any help would be greatly appreciated. Thank you in advance.
How familiar with the 7.3's are you? Your problem sounds like a common ICP sensor problem. Raise your hood and climb up where you can see the engine. Look towards the front of the Driver side head, just under where the valve cover bolts to the head. You will see a sensor and its plug screwed into the head. If you unplug this the truck should crank right but will be in limp mode. It will drive and get you home but won't have the power or smoothness your used to. Also look at the plug, if its full of motor oil that is another sign of a bad sensor. Pick up another sensor and replace. You will loose couple oz oil but nothing to worry about. Make sure area is clean of trash, grit, dirt etc... before removing sensor. That oil valley is direct feed to the injectors and you do not want dirt ruining a $400 injector. Try this out and let me know and we will move on from there.
On a 7.3 a good thing to keep in the tool box is an extra ICP,CPS, IPR sensor. Also there is some other stuff you should unplug and forget about to avoid future head aches but that is a for another day.
Sorry for the double post (I messed up on the edit attempt) but if memory serves me correctly, there is no tranny temp shut off on a 7.3. You can boil the fluid clean out of the tranny and the 7.3 will keep trying to pull. The computer will send you into limp mode to attempt to keep the 7.3 from totally destroying the tranny but it will not shut off.
Problem is most likely the IPR. Very common sign is the truck suddenly stalls as it's coming up to operating temperatures, as the OP indicated.
If it's at the dealer they should find the problem if they have a diesel tech worth his salt.
For the shadetree mechanic with proper diagnostic tools (such as AE or similar), when it stalls like this you can crank the truck continuously for 15-20 seconds. That is long enough to get the PCM to set the correct code for low ICP, indicating the IPR is stuck and not functioning properly.
Hope this helps. It's a somewhat common occurrence especially if the IPR has never been replaced and you get some miles and age on the truck.
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
