Looking for some help diagnosing my truck, please. I've got a '97 7.3 5 speed with 190k on it, basically stock other than a Superchips programmer. Left home this morning, was pulling up to a stop sign 5 mins from the house and when I slowed down the truck stalled - acted like it was starved for fuel. Started when cranked but had to keep pedal at half throttle to keep truck running. After 10 seconds or so it went back to normal and I drove the other 10 mins to work. After sitting 10 hours it started normally, then died off. Same deal, had to hold throttle in for 10 seconds and it took off running normally. Ran fine on the way home except for a brief hiccup while driving along at 55 mph - half a second at most. Only code the programmer picked up was P0236, turbo boost sensor A Circ Perf.

Only thing under the hood that looks out of order is the sensor coming out of the back of the high pressure oil reservoir, about half way up on the rear driver's side of reservoir - two wires and it's pretty well soaked in oil. Some fuel in the valley below lift pump, but not much. CPS is a year or two old, a black one if I recall correctly from the IH dealer.

Any advice is greatly appreciated, thanks.

 

Check all the UVCH plugs for burnt pins.

 

Thank you for the response. Would the pins be burnt where the harness attaches to the valve cover gasket, or elsewhere?

Also, I've read where others experienced these symptoms with a bad ICP, IPR or IDM. Anyone have a link to a method of troubleshooting these parts?

Thanks.

 

Pins could be burnt on either side. IDM O rings could be bad?

 

Thank you, I apprecite the clarification.

Never knew the IDM had o-rings on it.

 

Oh, I'm sorry, I meant the IPR O rings.

I'm should delete that post before I get laughed out of here,

 

Changed the fuel filter lately?

 

Hell, you had me! I was going to go looking for them, thanks for saving me some time!

Probably 10k on fuel filter, it's so sporatic I wouldn't think the fuel filter would be the culprit.

It needs glow plugs anyways so I'm picking them up this afternoon and will check all the UVC wires when I put them in.

Thanks for the advice so far.

 

Still looking for diagnostic help.

Put new glow plugs in the truck, one UVCH had some burnt glow plug pins, so I replaced it as well as the valve cover gasket. Replaced the lift pump as it was starting to weep, new CPS and fresh fuel filter. Also replaced the oil temp sending unit on the back of the HPOP, and NAPA is getting me the harness for the oil temp sensor as one of the wires is missing some insulation.

Truck fired right up and ran like a top, let it run for 15 mins while putting tools away. Drove truck into town an hour later, behaved normal. Truck sat outside restaurant for an hour or so, and had a terrible time starting. Had to start it 5 or more times, each time it'd die off like it was starving for fuel. Mashing the throttle helped a bit, but it had to clear up on it's own, then it drove home like nothing happened.

Checked the codes when I got home and got a P1280 - ICP out of range low. How do I go about seeing whether I need an ICP, IPR or something else? IDM maybe?

Any help would be greatly appreciated, thanks.

 

Next time it does it, unplug the ICP sensor and see how it idles.

 

Is that the end of the story? My truck seems to be having a similar problem...p1280 and running rough.