Not sure where exactly to post this, electrical or 5.4, so bump it if it'll do better somewhere else.
I have a '97 Expedition with the 5.4L, 2wheel drive, automatic. It has 234,000 miles and has been practically trouble free it's whole life. I've had to replace front rotors, one COP on number three, one ball joint, the alternator, and the rest was general maintenance stuff like filters, fluids, and a battery.
The problem I started noticing about a week ago is that when the key is turned, the starter engages and just drags a couple of times then spins like it ought to and it fires up. When the vehicle it turned off with the engine at full operating temp, like at a gas stop, it almost doesn't restart. That is when it mimics a low battery. But it always seems to get that last "umph" and spin it over and start the engine. Hot starts seem real difficult. Yesterday, during a hot start, the starter drug to a stop enought to kill all the power and affected the electricals so much that the radio went blank and I had to re-set all the presets, but it did finally spin it over and start. So I guess the problem is progressively getting worse. Hot starts are worse than cold starts, but the problem exists all times. I've checked the battery and it passed. It's four years old and it is a seven year battery. The cable ends and the posts are clean and have zero corrosion. I do notice at the starter that the exposed end of the copper ground cable does have the copper green tarnishing so I jumped in another ground cable just to check and the condition still exsisted. I am having the battery load tested again today at a different location, just in case. But once it gets past the initial drag, it spins like it has plenty of juice. Is this how a starter acts when it starts going bad? With the related radio stuff, am I having problems with the ignition switch? I'm open to any and all suggestions! Thanks for all info provided!

 

The cheapest thing to do first is even though the cables look corrosion free go ahead and pull them loose and run some abrasive on both male and female ends at ALL points from the battery to the starter and check the wires for chaffing. Then take it to have it checked for codes. After that try a starter, solenoid (sp?), and check the alternator.

 

Thanks for the suggestions. That is part of my routine maintenance. The only so called corrosion that I can find is on the cable that connects to the starter, at the starter. The wire is green under the insullation and I can see just a little of it at the edge of the insullation. The rest is clean as a pin and coated with ele. grease to prevent corrosion. I used another cable to bypass the one on the vehicle to rule out that the cable was excessively resistent.
Thanks for reminding me. I forgot to mention that throughout this whole ordeal, the thing hasn't thrown a single diagnostic code! I would have thought the check engine light would have been going crazy by now.
I'm headed out to get the meter and check the solenoid now. That would be great if that is what the cause is. Cheap fix! Cheapest starter I can locate is $112 rebuilt!

 

Yeah, you can't go wrong with cleaning the terminals. Be sure to take them all apart and chean even the ones that look fine. That's usually the one it is. As far as the starter goes it may be a shortage happening in the actual unit. Can you buy one anyplace and return it if you don't need it? Call around and see if a local mechanics shop has a donor starter to test out your vehicle or if a friend with a 5.4 or 4.6 will let you borrow his. If it starts fine a few times then go buy a new one.

 

Yes a failing starter can do this. Have the battery load tested as well as the starter. AutoZone will check them for free, in the vehicle.

 

I had a similar problem with my 97 5.4L f150, it eventually led to power loss and turned out to be an ignition coil that had to be replaced and it totally fixed the problem.

 

Did yours cause the check engine light to indicate a fault code?

 

The check engine light came on eventually, i think at about the time the coil totally crapped out. I had the slow start thing for at least a month or two before that, I had just assumed the truck was getting old. They replaced the ignition plug too, but I had to take it back in after that and they replaced the coil, they were both pretty dirty

 

Well, I finally got mine figured out today. Turned out it was a problem with the battery. Not sure exactly what, cause it held up to a load test like it's supposed to, twice! Must be a loose plate, broke posts, or something internal that's causing a lot of resistance. Anyway, swapped in the new battery out of the CJ5 and all is well.......except for having to buy a new battery! Never flashed the check engine light ever on this one. One of my coils (COP) went south and caused the check engine light to come on a while back. At first, I thought the engine was fried. Ran like it was on four cylinders instead of eight. Never thought one coil could make the engine run so crappy!

 

Glad you got it figured out.