Went to visit my folks this weekend. Ran great all the way there, bout 130 miles. Yesterday I went to leave my friend's ranch, got about 5 miles down the road and the truck died. Just like you turned off the key. Then wouldn't start back up. Bumped the starter to see if the lift pump was working and nothing. Though it was running 12 psi when the truck died. Completely unhooked the Edge and still nothing so I know that wasn't the problem. We hooked a chain on and started towing it back to the house. Got 1/2 mile down the road and it fired right back up.
Left the Edge unhooked and drove it the rest of the day off an on, probably about 50 miles or so and no more problems. This morning I got in it to come home. Made it about 8 miles down the road and it died again. Same thing, just sit there and crank, lift pump wouldn't kick on. Got out and wiggled some wires around and checked the battery connections. Got back in and it fired right up. Drove the rest of the way home, about 100 miles without a hiccup.

I'm going to check all my grounds tomorow. That's about the only thing I can come up with. Didn't throw any codes at all. Any other ideas?

 

Don't see anything in your mods about a lift pump upgrade--you still running the stock setup? Knowing what I know now about these trucks, if I ever buy another one a complete fuel system upgrade will be my first mod before anything else. You can see that by the mods listed in my signature on the truck I sold. The stock lift pump is extremely unreliable, and what makes it even more so is the fact that it has to pull fuel so far forward and so far up from the tank. Best to have a good aftermarket lift pump on the frame rail back by the tank so it can do more pushing and less pulling.

It's also very possible the PCM (Powertrain Control Module) is screwing up. The driver/relay for the lift pump is located there. This is one of the problems I was starting to have right before I let my '01.5 go. If this is the case you can either replace the PCM (don't know what the cost would be) or locate the wire from it that feeds the lift pump, cut it, and connect it to a source of power that turns on/off with the key. Good luck!

 

I do still have the stock Carter pump on the block. I'm pretty sure it's not the problem as it's still pushing 11-12 psi running down the road. I was also under the impression these trucks would still run with a bad lift pump, even though it's not good for them.

The PCM sure could be the problem. I'm pretty sure it's an electrical issue. If it was anything mechanical that failed, I can't see it starting back up and running fine for 100 miles to get home. I'm thinking there's a short somewhere. I didn't have a tester to check if the lift pump or injection pump were getting power or not. Now it's running fine, so I don't even know where to start testing really.

 

Not a short, but an intermittent connection somewhere. Sounding more and more like the PCM to me, but you're right--it can be a real pain to diagnose an intermittent problem. I talked with Diesel-Dan on here about the problem when I was having it, and he said the PCM failure was a common cause. And yes, the truck will still run with the lift pump not going--mine still ran but I would see the fuel pressure gauge drop to 0--problem is, your VP44 lift pump uses the excess fuel for cooling & lubrication, and if it's having to do all the work there is no excess. You're trashing your VP44, which may be why it shuts down on you from time to time. I'd bypass the lift pump driver on the PCM like I told you in my previous post (this is what Diesel-Dan recommended to me), and once you get the lift pump running reliably wait and see if the truck doesn't die on you anymore, and if it does die look at your fuel pressure immediately. If it's still up I'd say your injection pump is toasted.

 

Just thought I'd make sure you know so you're not barking up the wrong tree, the PCM (where the lift pump driver/relay is) is on the passenger side of the firewall behind your air filter. The computer mounted to the driver's side of the block is the ECM, and the FPCM is integral to the lift pump.

 

Even with a bad lift pump, the truck should start though shouldn't it? I honestly don't think the lift pump is bad. I don't think it's getting power, which could be the PCM like you're saying. I do have a spare lift pump harness I'll fix up to tie it straight in, but I really can't see that fixing it. I think the power to the lift pump is an effect of whatever's killing the truck, not the cause.

If the injection pump is shot, why would it run fine for 100 miles, die, run fine for another 50 miles, die, then run fine for another 100 miles?? That just doesn't make any sense to me.

Then again I could be completely wrong in all my thinking. It's been known to happen.

 

sometimes the lift pump failure will let fuel go thru it,but from the way you describe your problem i think you have a power supply problem

 

That's what I'm thinkin. Once I got it started again, the lift pump's running fine, putting out 15psi.

 

I wasn't arguing that the lift pump is bad; simply that you'll have an easier time finding out if it is if you have a more reliable source of power to it, or if that fixes the problem you'll know it's the PCM. And as far as a bad injection pump goes, some people experience different symptoms than others; some worse than others. I drove my truck for about a year and a half with a bad injection pump--even made a couple of trips to & from Tennessee (about 650 miles each way) pulling a trailer while I was helping my father move down there before I replaced the injection pump and upgraded to a FASS system. Without starting your truck, turn the key on/off/on/off/on, and write down all the codes you see flashing in the odometer window until it stops, and post them here. Someone will be able to tell you if you have one of the few codes you could get for a bad injection pump. I have a book I can look them up in if somebody else doesn't do it first. I sold my CTD Ram a little over a year ago, so I'm going from memory only on everything I've posted in this thread so there is a possibility I'm missing out on some other possible causes of your problem. Hope your problem isn't as bad as I think it is, but I wouldn't doubt that it is either.

 

I checked the codes with the odometer and my Superchips tuner. Neither shows any codes.

I'll be looking in to it further tonight after work.

 

Anyone have a wiring diagram for the PCM?

 

Mine was kinda doing the same thing......It was my crank sensor....

 

It's been running fine since I originally posted this. Just took it to the dealer on Monday. Wasn't showing any codes on my scanner, but theirs showed a code for the injection pump. Got a new pump on it's way. Dealer wanted $2800 for the pump and install. Told em to give me my keys...lol

If it was the crank sensor it should have thrown a code shouldn't it? Worth looking in to at least.

 

The fuel injection pump relay is located in the Power Distribution Center (PDC) Refer to label under PDC cover for relay location. Check for any codes first but swap out this relay. I had this relay go bad would cause same problem. There are several injection pump codes which code did they pull?

 

Just an FYI, sometimes the truck won't run with a bad lift pump. I just changed mine out a few weeks ago (got a fortunate 135k out of the stock one before replacing), but it would die out on me and leave me on the side of the road as it did for you. Sometimes it would crank right back up, other times I would sit for 30 minutes before it would crank. Now with a new lift pump, all is well.