2002 F250 7.3L suddenly idling and running very rough, and doesn't have any power.

Truck has been running perfect, it's my daily driver, and just put a couple hundred miles on it yesterday with no problems. I had been having some transmission issues when I tow heavy so I bought a new transmission yesterday. This morning I pulled the truck into my garage to change the transmission. Again truck ran fine, no signs of any issues before the trans swap. I changed out the transmission, which included unhooking the trans wiring harness from all the various sensors, and unbolting the starter. I didn't mess with anything in the engine bay except for unhooking the batteries. I had also repaired the overdrive button wires, as they had been pinched in the steering column and the button wasn't working. When I got everything hooked back up I cranked it up to get the trans fluid flowing through the transmission, it started right up and idled good. I had it running for a few minutes and it was beginning to make a little more noise than usual. When I started to back out of the garage it was getting pretty rough, almost like it was running out of diesel. I put it in neutral and gave it some throttle and noticed I was getting white smoke out of the exhaust and could smell diesel pretty strong.

I checked my injector resistance at the valve covers and got around 4 ohms +/- on all of the injectors. I rechecked all of the clips and harness that I had messed with. I took a look at the ICP sensor and it has oil in the connector which I know can cause a rough running condition in some cases. It looks like it has had oil on it for a while. I unhooked the batteries again for about 20 minutes to try and reset anything that may have messed up. I checked a bunch of connections under the hood to see if anything was unhooked or loose. I also cleaned up the connector on the ICP sensor. I started the truck back up and it idled perfect so I pulled it back out of the garage and headed down the driveway. It almost immediately started running rough again and barely had the power to go up a small hill. I pulled back in and tried unplugging the ICP while it was running, which made a slight difference in the idle but still very rough. I plugged it back in and the idle progressively got worse until it was chugging really bad. I shut it off after that and haven't messed with it again.

Does anyone have any ideas on what might have happened? Could it be a bad sensor or transmission position sensor in the new trans? Is it just coincidence that this happened with a transmission swap? I am going to get a new ICP, but if there is anything else I can try/check before I can pick up the ICP on Monday let me know.

Thanks in advance,
Jason

 

I figured it out. The truck is back to normal...

I dropped the tank and found that the plastic sending unit/pickup tube had broken off so it wasn't sucking diesel from the bottom of the tank. I only had about 1/8 tank of fuel so it was sucking air depending on the angle the truck was sitting at. The screen filters were also clogged up pretty bad.