We have a 2002 Excursion XLT. 7.3 liter diesel. Edge chip.

It started turning over slowly when starting, and before I could take it in, it stopped starting completely. We tried jump starting it, nothing. the batteries seemed okay, so we took the starter down to the auto parts store and had it bench tested. It tested fine. We didn't think it would be the starter, since it is just under two years old. Didn't think the alternator was at fault, since it is a year old. Purchased a new relay and installed it in the inside fuse box, nothing. We purchased two new batteries. After we dealt with rapidly flashing 'theft' light on the dash, it started up. Thought we had solved the problem. A couple of days later, slow to turn over when starting again. The next morning it wouldn't turn over at all. Tried to bypass all the sensors and relays between the ignition switch and the starter by connecting a wire between battery and starter. Nothing. Had starter bench tested at a different store. It worked intermitently. Replaced the starter. Nothing. But when we hook up the battery directly to starter with key turned it turns over AND starts. Assume it something in ignition switch or a relay between ignition and starter. Bought a manual, but it doesn't show where to find relays. When I check trouble codes, I have a p1000, a p1260, a p0603, and a p0674.

Can anyone offer a miraculously easy solution?

 

I recommend check out the 7.3 L Diesel section
1999 - 2003 7.3L Power Stroke Diesel - Ford Truck Enthusiasts Forums

We are too busy telling each other why we bought the Excursion

 

Everything you describe sounds like a charging issue to me. When an engine is slow to crank it usually means a lack of current to the starter. The first step is to check voltage at the batteries, which you don't mention having done. Without seeing how you tried jump starting it and no knowledge of your mechanical aptitude, I still suspect weak batteries. You say the batteries "seemed okay", but I don't know what that means. Your alternator is the likely culprit, regardless of it being only a year old. I have seen too many alternators that were dead well before the one year mark. I am curious as to why you replaced the batteries if they looked okay, but the new batteries did solve the issue temporarily. That tells me that they were fully charged and flowing sufficient current to start the engine normally for a couple days. Again, this is indicative of a charging problem. As for replacing relays, I think you are on the wrong path. A relay is simply an electrical switch, so it is either flowing current or it is not. It would be unusual to have one flow only partial current. As for the starter, you replaced it and it changed nothing. Again, this points to weak batteries. The only thing that puzzles me is the last part when you hook a battery directly to the starter. Was that the battery in the truck?

This all leads me to ask if you have recharged the batteries? If so, have you checked voltage at the starter when you are attempting to crank the engine? That would be the first place to start. If the batteries are FULLY charged and you don't have close to the same voltage at the starter then you need to start working your way backward from the starter, checking voltage at each point.

Like I said, I don't know your level of mechanical aptitude or experience, so please take all this advice with that in mind.

 

That or bad connections - loose or corroded ground.

 

Hey there - thanks for the responses. I am only a little mechanically inclined... I forgot to mention that I took the new batteries in and had them charged after we couldn't start it the second time. At that point I assumed it was the alternator not charging the batteries, but was surprised when it wouldn't turn over when I reinstalled the charged batteries. I don't have a multimeter, will have to purchase one in order to check voltage. We started it by attaching the battery in the vehicle to the starter. I have cleaned the terminals and cables well. But did not check the ground connection wherever it attaches to the chassis. It does start when we jump the starter, though, and that confuses me. Shouldn't that mean the batteries are charged and it is grounded? That is why I was thinking relay or sensor between the ignition switch and the starter....

 

Oh - and my father-in-law and I checked the old batteries the first go around with his multimeter, and his hydrometer. Voltage was at about 12volts, but hydrometer said the cells might be heading south.

 

Invest in a good one, then like I said, check voltage at the starter when trying to crank the engine. Work you way back from there.

If you still have them, sell your old batteries on craigslist to recoup some of your money.

 

I had exact same problem recently. It was the Alternator only putting out 10.8-11.8 volts and not recharging the batteries. Took a week, but the batteries would slowly die and the engine would turn over slower and slower until it wouldn't start. I thought I had a parasitic drain, but it was just the alternator going south.

 

Make you are getting 14.3v with engine running