I drive a 2002 F250 7.3 L. The other day I was driving home, when the electrical systems in the truck started to die. The radio turned off, the interior lights started to dim, and finally the truck completely died. I assumed it was the alternator, so I had it towed to a mechanic and they confirmed that it was. I went with a friend to drive it home (they came with me to jump me, if it died while driving home), and the truck made it all the way home without dying.
I changed out the alternator with a remanufactured one that I got from Advanced Auto Parts, Tough One brand. So, once I did that I tried to crank up the truck and it wouldn't start. It was trying to turn over, but couldn't fire up. I tried to start it a few times, but it wouldn't work, so I stopped and decided to try and charge up the batteries. I figured they were drained from the drive home. Once the batteries were fully charged (they're currently both reading 12.77 V), I tried to crank it up again but it wouldn't fire up.
So, now I have no idea what to do. My only theories are that the starter is bad, or maybe the glow plugs (it's maybe 60 degrees out now). I tried hitting the starter before and during cranking and that did nothing. So if anyone has any idea what could possibly be wrong, please let me know. I'm going to call a few mechanics tomorrow, but in the mean time I could really use any input.

Thank you for any help or advice!

 

So, are you getting lights and electrics now or no? Is the truck cranking at all or just clicking and nothing? Did you check all your fuses in relation to the ignition and alternator?

 

All of the electrical systems in the truck are working, yes. And it cranks, kind of like it does when it's cold and it takes a while to start up, but it won't start. It's almost like it's "hopping" if that makes sense, while I'm cranking it

 

I'm assuming you have a block heater try plugging it in for a little and starting it. I just did glow plugs and only for a week later my glow plug module to fail on me.


maybe your plugs arent getting warm enough without extra help. due to the GPR / GPM failing

 

How can I check if the glow plugs are working? I just check the glow plug relay with my multimeter and it was working fine

 

You try plugging it in and starting it

 

Charge the batteries individually, and check each one individually. When mine were hooked up they tested fine but when I pulled them and tested them individually one was shot and one would only take a charge up to 70% .

 

I believe the 02 has battery to fuse box connection point under the air filter housing on top of the inner fender well that is prone to corrosion might be worth looking into.

 

Turn the key on while monitoring battery voltage. If the glow plugs are working you will see the voltage drop down around 11 volts. Another way is to closely watch the dome light, it will dim slightly when the glow plugs kick in.

 

How many miles on the injectors? What oil are you using? Have you checked all your battery connections, including both grounds to the block? How long do you let the GPs burn before cranking?

The last link in my signature helps with slow/no starts.