First time this has ever happened to me - i turned the truck off after being at full operating temp. then, jumped back in to pick up another load of free firewood about 15 mins after shutting it down but it wouldn't fire up again.

WTS light came on, then off as normal, tach was up around 200-300 rpm while cranking, but no smoke from tailpipe at all.

assuming the problem was in the injection system (fuel or HPOP) and using DIYMechanic's no-start flow-chart, i found the following:

plenty of oil on the dipstick - added a quart for good mesaure just to bring it up to the full line
no blown fuses
good fuel pressure - ~50 psi while cranking
fuel bowl is full and clean (just good old green diesel color)
unplugging ICP sensor does not help (no oil in sensor connector)
IPR wires in good shape (just put new connector on a few months ago and wiring still good)
tin nut on IPR is tight
no obvious HP oil leaks on the cylinder heads or connections

BUT - after cranking maybe 5 times all with the same results, i found that the HPOP reservior was quite low. i could see oil in it, but it was 3" down below the upper surface of the HPOP. i've read that 1" or less is normal and that anything less indicates a problem with either the HPOP or the IPR. how do you tell which one is the problem, though?

suspecting that this 'hot no start' issue is perhaps due to a failing IPR and/or HPOP and that thicker/cold oil might help the situation, i let it sit for about 5 hours and then tried it again.

started on the second crank that time and then ran fine. i warmed it up by driving around a bit (hoping to pick up the free firewood, but it was gone! darn!) parked it, let it sit ~15 mins and tried to start again. this time it starts right back up again. shut er down and checked the HPOP reservoir right away out of curiosity - right up at the top this time.

Sooooooo - anyone have any advice as to how i might determine if its the IPR or HPOP that is the culprit - or maybe something else altogether that i'm overlooking? i don't have a scanner, but have been meaning to buy one for a while. could i answer the question for sure if i had one?

or at this point (with 195k miles), should i just replace the HPOP and IPR together and be done with it - and hopefully not get stuck somewhere away from home and have to wait for the truck to cool down to get home.

one related note - ever since i've had the truck (2 years), it has had a slight up and down idle. barely noticable tach movement, more of just a sound/vibration change - i actually hear it most in the sheetmetal of my cross-bed toolbox. i think i've read that this could indicated a failing IPR as well. is this true or am i making this up? its never stalled on me, but i also don't know the IPR duty cycle at any benchmark conditions. it does have plenty of power at wide-open-throttle,t hough.

as usual - any/all input/advice is greatly appreciated.

 

Have you changed the CPS since you've had the truck?

 

hey bill - thanks for reading

nope - haven't changed it, but it is a black one and i thought that the solid 2-300 rpm when cranking indcates the cps is reading OK. is that not true?

i've been meaning to pick up a spare though, so maybe this is the push i need.

any thoughts on HP oil issues, though or am i way off on that?

 

Change your IPR O rings. Check the level in your hpop after it sits all night to see if its draining down.

 

Hey bud! You're not way off I don't think on it being an oil issue, but the CPS can do strange things sometimes, and it's much cheaper to try as a solution. Seems like I have read you can still see the tach moving in certain instances, and still have a bad CPS. If you get another one, and that's not the problem, you'll have your spare.

 

Pull the ipr and check the little oring on the end. If that's in good condition then its injector orings.

 

interesting - that is a much cheaper fix than a new IPR or HPOP. hopefully that's it. seems like a bear to get that thing out of there, though - i've read about the removal of the back half and then use of a deepset 1-1/8" socket over the body to remove it. ...not looking forward to that job at all. and good call - i'll be keeping an eye on the HPOP oil level from now on and especially after an attempted fix...

definitely the easiest fix - and yep a spare if not the fix

wouldnt bad injector o-rings have other signs as well? like oil in the fuel bowl and slow loss of oil?

anyway, i broke down and order a scanner tonight. i'll probably order a CPS as well. been meaning to for a long time.

thanks for the input guys. keep it coming!

 

The deep dish socket, I read, has to be a sears or another one that I can't think of now. I got the sears and it works good.

 

I posted it on here, and I don't know if anyone believed it or not, but I changed my IPR with a 1 1/8" wrench, and without removing the fuel bowl. You have to be very patient to do it. LOL!!!

 

You, have patientence? What, it took you about five minutes, huh? A guy who pulled his motor on his lunch break can take a IPR out in a couple of minutes with the fuel bowl in. LOL

 

LOL!! I do have patience sometimes. I'll admit, not all the time, and NEVER according to my wife! LOL!! I guess it depends on what kind of mood I'm in. Some days I can do stuff like that, and other days I'd wanna rip the whole front of the truck off with my bare hands! LOL!! As I've gotten older though, I've learned when to just lay the tools down and walk away for a while.

 

That's exactly what I've learned, walk away for awhile. Wrenches thru windshields get expensive, don't ask.

 

Shop windows aren't cheap either

 

Ya, when I was unable to get mine to fire that first night I threw a pair of sunglasses into the wall. I SO wanted to grab the ratchet laying right beside it and throw it, but I held back.

I should have went home 2 hours earlier...

 

well - i checked the HPOP reservoir twice more over the weekend. after sitting overnight on Friday, it was full on sat morning. then, i drove the truck for some errands sat morning, got it good and hot, then let it sit until Sunday afternoon. reservoir was still full. maybe it was just a freak occurance?

for good measure i changed the oil yesterday anyway. it was about due and i thought some new, thicker oil would at least postpone this problem from cropping up again...