I have a 1993 ford diesel 7.3 diesel 257,000 kms. Recentley it would not start after warming up. The mechanic said it was glow plugs. All glow plugs were changed and it started easily 5 or 6 times.
After driving for a short time it would not start. The mechanic changed out the glow plug relay and again it started fine 5 or 6 times. Again after driving for a short time it would not start, just turned over.
I took it to another mechanic who has had it for a week and driven it all over and can find nothing wrong. He says starts good has good fuel pressure so they don't know what to do. I had them change the fuel filter in case something poor in the fuel. But now I don't trust the truck to start if we take it out.
It has cost me well over 300 dollars in tows. It just turns over like it is not getting fuel. I never smell diesel like you would in a gas engine that is flooding. It appears to start fine cold but when you drive it and shut it down a few times it decides not to start just turn over. I really need to figure this out as it is my only vehicle

Thanks

Thoughts:

. Check engine oil level--ensure it's filled to the top line. This affects fuel pressure.

. Check the fuel injectors. Take the valve cover off and look at the exhaust part of the injector when it is running. Each time the injector fires, you should see oil exhausting from it. If you see oil coming out, then the injector is good. When replacing a bad injector, take the glow plug out and crank the engine to get any oil out of the cylinder. If you don't, you could hydro-lock and bend a rod.

. Purge fuel filter or fuel separator of water. Do this at least monthly--daily, if necessary. Water can be a big problem with diesels.

. Use synthetic heavy duty engine oil. Installing a by-pass oil filter makes using top-quality synthetics very cost effective, when integrated with a used oil analysis (UOA) program. All engines run better on synthetics, particularly turbo diesels. Besides significantly improved engine life, turbo life, performance, and gas mileage, synthetics promote easier starting, by allowing increased cranking speed. This last factor is particularly important in cold weather. Synthetics are also easier on batteries and starter motors.

. Clean battery terminals and connections.

. Ensure both batteries are fully charged, after checking fluid levels.

. Replace air filter.

Keep me posted.

P.S. It's easy to change the transmission fluid on PSDs. Drain and clean the pan (gasket is reuseable), change the filter, remove the cover plate and drain the torque converter, and refill with ATF. I use Mobil 1 Synthetic ATF, which makes a big difference. There's nothing like a well-maintained diesel truck!

I don't know if you have fixed the truck yet, but I would replace the cam sensor, then the ipr, injection pressure regulator. That should fix your problem.