95 7.3L - Won't Start When Warm

[Snoopy]

Hi All,
I am new to this forum, but have owned my truck for the last 10 years.

1995 Ford F-250
Super Cab
5-Speed Manual Trans
85,000 mi.

The problem is a no start situation when the truck warms up. It fires up just fine when it is cold and will start after it is allowed to cool down. Once it is running it will run all day long without a problem, as long as I don't shut it off.

I took it to the local Ford dealer and he ran it on the computer and found no problem codes. He was sure that it was the cam position sensor. I didn't think the CPS was the problem because the tach was showing about a 100 RPM while cranking. I replaced the CPS and still have the same problem.

I checked the oil level in the high pressure reservoir and it was about a 1/2" below the lowest thread in the plug hole.

I replaced the fuel filter and the bowl was clean. The filter housing fills up quickly.

I would appreciate any help with this problem.

Thanks

[Logan]

Not sure what to tell ya Snoopy, but I can do this



To POWERSTROKE.ORG

[alfajay]

HI all kinda new, been ready more than responding. Anyway to respond to your ?, I had a bronco back in the day and it had a problem, it was the temp sensor. There was 2 of them on the bronco it was the elec. one. I went to a auto diag. place and they told me it was a $300 fix they could do that day. I went to Advanced and bought the part for $20.

[Snoopy]

alfajay,
Is there anyway to check out the sensor without replacing it?

brrs3633,
Thanks for the welcome and the bump.

[LTFOX]

Snoopy, I 'll bet it s the orings on the end of your IPR. I've seen several this way. The orings blow out and with cold oil your HPOP can still build pressure to start, but when warm the thinner oil goes past the orings and the truck won't build enough pressure to fire.
Here is a link about the IPR.
New Page 0

[mschn99]

Originally Posted by LTFOX

Snoopy, I 'll bet it s the orings on the end of your IPR. I've seen several this way. The orings blow out and with cold oil your HPOP can still build pressure to start, but when warm the thinner oil goes past the orings and the truck won't build enough pressure to fire.
Here is a link about the IPR.
New Page 0

I second this....ive only seen it a few times but thats the only time ive really ever seen a 7.3 be a consistant no start after a hot soak....

[Snoopy]

LTFOX,
Thanks for the information and the link.
This has been driving me nuts for about 3 weeks. The truck starts easily when it is cold. But as soon as the temp gauge needle starts moving, the engine will not start. The engine doesn't have to be hot, it just needs to be warm for the problem to show up. Idling the engine for 4 minutes gets it warm enough to cause a no start condition. I just couldn't wrap my mind around the fact that after starting, the truck would run flawlessly all day long, I just drove 180 miles and experienced no problems.

I will see if I can locate a socket for the IPR removal and see if the o-rings are the problem.

Marc,
Thanks for the backup.

Does anyone know the part numbers for the o-rings?

Thanks for the help.

[LTFOX]

IPR O-Ring Kit (for when IPR valve replacement is not required)
(Ford) F6TZ-9C977-AN (F6TZ-9C977-AA?)
(International) 1825806C92 (1825806C91?)


Here is a link for ya to save....powerstroke part #'s!
PSD_Part_Numbers

[Snoopy]

LTFOX,
Thanks for the link. I will order the fit tomorrow. When I get it I will pull the IPR and see if it is the problem. I will post my findings.

Thanks all for the help.

[Snoopy]

Where do I find the engine serial number and the high pressure oil pump part number? Just in case I need to replace the IPR.

IPR Injection Pressure Regulator
(Ford) F4TZ-9C968-C (engine serial no. 187099 & before or pump no. 255C92)
(Ford) F81Z-9C968-AA (engine serial no. 187100 & up or pump no. 247C91)

Thanks