Hi all, Noob here and I am very happy to see all the things I am experiencing here so I can start fixin'. My '03 F-350 7.3 4x4 has had me scratchin' my head 5 or 6 times this year. I have 137k+ miles on it. I'll drive somewhere, park for 10 minutes or so and when I try to start it'll crank like there is no tomorrow but won't start. Then after fooling for 20-30 mins it starts. By fooling I mean checking fuses, battery connections, pushing/pulling on wiring harnesses and connectors. No one thing seems to fix it. I've read about the CPS, Low Voltage, Fuel Pump but don't read anywhere that these things could be intermittent. My WTS light works and I hear what seems to be all the normal noises when I turn the key on. Oil level is good, plenty o' fuel. What if any or all of these things be intermittent as described or where to start lookin'? Thanks.

 

Welcome to the site,
There is a wiring harness over the drivers side valve cover that can rub on the valve cover and short. you can check that. I had a problem with a short and took apart all the connectors and used a small amount of dielectric grease on them and fixed my problem. A Curtis

 

Welcome to FTE. I have a similar issue but it always starts after turning the key to off and then retrying. Wish I could help. Here is a bump back to the top though.

 

Happened again today on my way to the shop to do some troubleshooting. I stopped for some lunch and no start. I did a quick visual on the harness over the DS VC and did not see or feel any broken wires. So after I ate my lunch I tinkered and eventually it fired. I've tried different key positions, moving it to neutral, standing on my head and nothing seems to work. Know of any heat related reasons it wouldn't start? That 20-30 minutes is enough time for something to cool. Problem is its only intermittent and of course never happens at the shop.

 

I'd suggest you have someone turn the key on while you lay under the truck or at least crouch down beside the drivers seat. Don't start, just turn the key on. Listen for the sound of the fuel pump. If you can't identify it by sound, it helps to place your hand on it when it comes on so you can isolate the noise. The fuel pump will shut off after about 25 seconds.

Once you're familiar with the fuel pump sound, always listen for it when you turn the key on. We need to know if the fuel pump comes on or stays off when you get your no start condition. This doesn't have anything to do with the fuel pump, but the power circuit that energizes the pump.

Other questions, do you have a chip in the truck? When you have a no start, is there any smoke coming out the tailpipe while cranking?

 

I will try that at next opportunity, possibly tomorrow when I have a second person around, and report back. Thanks.

No chip all stock. No smoke that I have seen. Honestly haven't looked for it.

 

Will it turn over but just not fire? One other thing to consider is that the HPOP could be draining as well.

Mine has left me stranded one time due to a drained HPOP. I had to get it towed. I ran down the batteries trying to start it. It would also start then die a few times then take a long time to crank indicating a bad HPOP checkvalve.

I also tried to start it today after sitting for months and had to stick a quart in the HPOP to light it off for a few seconds, then stick another quart in it to finally get it fired and keep it running....

 

Yes it cranks great. New batteries this summer. I had the experience of one of my batteries going bad and it would do the same thing. Crank but no start. I could jump the bad battery and it would fire. Replaced both batteries and no problems for several months until I was stranded on Thanksgiving. After about 30 minutes of trying and tinkering it started. Just in time to make turkey dinner. I checked my batteries yesterday and both passed. I did a load test and had a VOM on each as I cranked and both stayed at 10.9 or better. Of course while I was at the shop it wouldn't repeat problem.
How would one check the HPOP level?
Mine doesn't die while running. Only after I shut it off and it sits for a few minutes then try to restart. Once it starts it runs out fine. I haven't yet tried any other checks. When it repeats I have a list.

 

There is a small plug on the top of the HPOP cover. It has a hex drive on it. Pull it off WHILE THE ENGINE IS SHUT OFF!!!! and see the level.

I'd pull it when it will not start. It's possible oil could be draining out of it and when you try to start it the oil pump refills it which allows it to start.

Is the oil level OK? Fuel filter OK? Any codes?

Also, check that square connector on the driver's side valve cover. Mine had a bunch of corrosion in it at one time and caused some rough idling/running...

 

Thanks. I'll get my ready kit in place when it dies again. Is there a good manual (power stroke for Dummies or better) you can recommend?
Oil level is good. Change every 3k now.
I'll have to check maint log for fuel filter. Probably means too long since I can't remember.
Haven't checked for codes. The one time I had checked for codes when this happened they told me there were none. What should I expect to pay if I wanted to purchase a reader?

 

Splurged and bought Innova OBD2 today. Checked for stored codes and there were none. Still has not repeated problem. Changed fuel filter since it hadn't been logged and I couldn't remember the last change. Popped the check plug on the HPOP just for practice I guess since it was right there while changing the FF. Level was near top. Listened for fuel pump and got he sound stored in the memory for when it dies again. Next I'll grab a spare CPS. Thanks for all the tips so far.