My 2000 F350 7.3 won't start in cold weather, I'm talking about weather in the 40's, It started happening over a year ago. I posted on here back then and it was suggested I replace the GPR witch I did and it didn't change a thing. So last winter I had to plug in my block heater every night if it was going to get under 50 degrees.. So I also took it to a diesel repair shop, after 2 days they called and said come pick it up that they can't find anything wrong. When I picked it up I asked why can't they fix it? They said maybe it's because its an old truck??? I'm not going back to that shop ever again. Now I was just up in 6500 feet elevation last week, it got down to the low 30's. The first day it took me from 9:00 a.m. to 2:00 p.m till it finally started. I drove 30 miles one way and bought a new power cord for the block heater (when I plugged in the original one it would trip the breaker} I installed the new power supply, plugged it in and tripped the breaker. So the next day at 5:30 AM I put a propane heater under the oil pan. at 11:00 A.M. it started and I made the 8 hour drive home. Now I know I need to put a new block heater in. That will make sure I can start it this winter, but it doesn't fix the problem.. I just turned 200,000 miles on this last trip. I change my oil and filter every 3.000 miles. I don't have much faith in the shop that I took it to, but he did tell me that my glow plugs were okay?? This really sucks. Any help would be greatly appreciated, I plan on keeping this truck for at least another 100.000 miles, but I need it to start in the mornings. I bought the truck in 2002, I've had one injector replaced and the valve cover harness years ago both on the passenger side. Other then that no engine work. When it won't start it is putting out a lot of white un burnt fuel.Any thoughts? Other then find a different shop

 

I would ask how they determined that the glow plugs were good. I would start there ohming the glow plugs. At 200,000 miles have you ever replaced the glow plugs? Previous owner replaced? If you're not sure I would replace them with Motorcraft only. It's not that bad of a job.
Edit.. How long are you letting the glow plugs heat up before you try to crank it over? The glow plugs are activated for up to 90 seconds AFTER the wait to start light on the dash goes out.

 

 

I bought from a Ford dealer, no information about previous owner or previous repairs. No I haven't replaced any glow plugs. I'll try and google how to replace them. To be honest I'm not sure how to OHM them out?

 

Lol..doing the same thing. I carry a cord and a lightbulb plug socket for just in case. Got stuck in bigbear for no start. Took patio bulb out and screwed in socket. Let it warm up over night and oil was at 90* come 7am in 29* temp..lol. Also happened last october in mammoth. Just would not start. Had a window of sunlight from 10-2pm so left the hood up(camping at no hook ups).. Got it warm enuf to fire over....id say check glowplug relay and switch to 5/40 synthetic. Also, if gpr IS good, dont go by the WTS light. Wait until the seatbelt guy light goes out(almost 1.5min) because thats how long your gp's are staying lit...

 

I don't know what is causing your problem but I had a 1993 F350 with a natural 7.3 diesel and the glow plug relay would just click and wouldn't start. To get it started I gave it a shot of ether and crawled in and turned the key straight to start and it started. You DO NOT want to let those glow plugs get hot with ether. Mine would start on WD-40 also.
Did you or that garage check to see if current is actually going to the glow plugs?

 

Oh lord, not another ether advocate....
Read up on changing your GPs, buy 8 Motorcraft, start on em Saturday morning, take your time n clean everything under the hood as you go n you'll be done before dinner. Or skip the cleaning and be done by lunch. HIGHLY recommend retorqueing injectors while you are already there. Look up hot torque for info on that

 

DO NOT USE ETHER!! PERIOD

 

I asked but maybe you skimmed by. How long are you waiting after you turn on the switch before you try to crank it?

 

You can ohm out the glow plugs through the UVCH on each head. The two flat pins on each side of that plug feed the glow plugs. I can't recall the exact numbers you are looking for but I am thinking between 1.5 and 2.0 ohms, someone else probably knows exact numbers. As suggest above I would also test the GPR It should activate for up to two minutes depending on oil temp.

 

When it's a warm morning I turn and start. But when I know it's cold and I'm going to have problems I cycle the key about 10 times before I try to start it.

 

Another vote for zd-11 glow plugs and a glow plug relay. I went with the monster glow plug relay that Guzzle sells and haven't looked back since!

 

Ok, but that doesn't tell us how long you are leaving the key on after the wait to start light goes out. 1 second, 90? As stated that's about when the glow plugs come on, not when they go off.

Morons at Ford should have used a glow plug light instead of that confusing light.

When you ohm glow plugs you'll know when they are bad. They usually read 1-3 ohms when they are good, can nitpick exact ohms for UVHC issues. When they are bad they read thousands of ohms

 

I try to start it when the WTS light goes off. I didn't know I was supposed to wait longer then that?

 

check out carfax "maintenance" for free, it will show the previous shop maintenance with mileage