truck dies. no codes. no check engine light. restarts after 30 minutes
 

heya

Thanks for any advice!

'03 F250 7.3L

i bought my pickup a couple weeks ago. sometimes it just dies, just like the keys were shut off. no rough running. no codes. no smoke, no engine light. will not restart right away. after it cools down, it runs again (sometimes 10 minutes, sometimes 40 minutes). the water and tranny temp guages do not show too hot, just right in the middle always. maybe something sensing hot oil?

i have changed the CPS two times in the last two weeks. still dies. fresh oil 300 miles ago.

help! (thanks!)

Guy

Losing compression ?

I had a buddy that had that problem with his - it was an 03, i think, but had the V10 - it ended up being the wire loom - after he traded it somebody told him they had a bad batch of wire looms ??? :humm:

don't think i'm loosing compression. i haven't checked it however. I have wondered about the wiring, i do know people have replaced them (they cost a fortune). I have been told by others they think it's a short too. i've wiggled things, truck doesn't die. i've found a couple chaffed wires from the plastic loom scratching through insulation, and taped them up. weird thing to me, is if it dies, then doesn't start until it sits for a while, why would it be a short? (unless some sensor is getting hot or something, then why don't i get a code or why wouldn't someone say "it's your 'blank' sensor"?

I'll do some more checking based on these comments. keep 'em coming, i sure appreciate it!:ok1:

does it turn over at all?

Yup, turns over fine.

I do wonder... the electrical still seems to be the problem. i got thinking about the IPR, and i would expect some hesitation, not a simple "off". those connectors are awful small, and as i said, i have heard about the whole wire looms being replaced... i'll have to get out there again and wiggle at the connectors. those little pins at the back of the IPR maybe not connecting well. Maybe i can do another wiggle test with the truck running, and wiggle right at the connectors, and maybe make the problem happen. same with the cps, maybe i can poke down at it with a dowel while the engine's running. maybe the wires have broken inside the insulation at a kink point, like right at the connector.?

Pull the fuel filter cap off and check for fuel in the bowl as soon as it dies. Sounds like a fuel supply problem to me

first time it happened i checked fuel level, and changed filter (although it was just done on the last service). full of gas.

today i did some more wire testing (wriggle). I started the pickup, poked at the CPS wires with a stick, kept running. i wiggled all wires on top of the engine, kept running. I pulled the IPR plug off while running, it died just like it does when it dies on me. i pulled the plug, and things seemed fine. i don't like the tiny connectors. i wish i could buy a new one and wire it all the way as far as i can follow it, bypass the 42 pin connector and all. Not even ford sells plugs, gotta buy the whole wire loom on top of the engine, and they want a pretty-penny for it.

I tried to pinch down the connectors a little more, but i don't have anything small enough to get in there and pinch things down. heck, maybe i should jam some tiny piece of wood or plastic in there to make a tighter connection.

any new ideas? Thanks people!

Guy

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UPDATE

well, i took it for a drive, and it did die after it got hot. I iced the IPR, with two ice cubes, nothing. i wiggled wires, nothing. i iced CPS nothing. i iced anything that looked like a sensor or was hot (all HPOP related things hot). nothing.

i unplugged IPR and plugged back in, it started. Guess i'll try that first next time. now i don't know if that connector is assuredly bad, but if it is, and it fixes it next time, i'll better know. any new thoughts?

sounds like you were pretty lucky finding plug - hope the next time it dies on ya that fixes it. Would be nice to have your prob solved that easy!! :U:

thanks!

ya know, i did some more driving and testing, pretty sure it's the plug. if not, then IPR...
i tell ya what happened tonight. i tried the ice trick, and such... (long post)

I drove it until it died. i iced wiggled wires, and between it all, i was running again in 10 minutes (compared to two dies yesterday, and 40 minutes each). It seemed to me the icing of the IPR and wiggling the IPR connector was more of what helped, the last thing i did was unplug and plug in the IPR, and it started.

I drove again until it died, and that time i only focussed on the IPR only. I unplugged and plugged in the IPR, did not start. I iced it down, and it started. (all the area, HPOP and lines are very hot, but the IPR really isn't that hot (nothing running through it) i'm thinking if i were to tap it, it may unstick just like cooling with ice)

I drove it home, and in the driveway while running, i crawled up, wiggled the connector only (not wires) and it died in my hands. kept trying to start and wiggle, no go. even pulled out the gasket, did not start. I iced it down, and it started. all within 5 minutes.

my conclusion at this point: wire connector bad, and when it shorts, the IPR sticks. icing cools it down and "frees" it from sticking, so it runs again. I guess that simply fixing the connector would solve the problem, but i cannot buy a connector separate from the harness. So i'm thinking about somehow getting some new connector ends (maybe radio shack?) clipped on tight to the IPR. I wish i could get to those pins in the IPR, i'd solder on wires directly.

next time i drive it, when it's cold, i'm going to try to kill it with wiggling that connector.

any new thoughts with this information? Thanks!