I have scoured this site for answers and there are many but now I need some opinions. 2002 F250 with 7.3, 313 thousand miles. Got starter rebuilt by reputable place 3 years ago, about 50 thousand miles ago. Now I am randomly having a no response when I turn the key occasionally. Sometimes it will do it 5 times a day. The very first time I crank it after has been sitting it will crank just fine. If it is cold though and I have to let off the key it may do absolutely nothing starter wise when turn the key again. It does all of the other normal things that the key controls, radio, lights (lights do not dim when turned to start position). Problem is worse when it is cold. When it DOES start to crank it cranks perfectly. Batteries are good. Sometimes when it starts acting up I will have to turn key 100 plus times and then all of a sudden it will just turn over fine. If I let it sit usually when I come back and try to start it will fire right up. I cannot check the voltage of the wire to the starter solenoid because there is no one to help me and problem is so intermittent. I changed the starter relay in fuse box already, no change. From what I am reading it is either the ignition or starter. Which should I change first and how big of deal is changing the ignition?

 

I have had a similar issue. Last year, I was going to start the truck in 0 degree weather and same thing, no click, no starter turning, nothing. Long story short, I started the truck by jumping the starter solenoid with a long screwdriver. I ended up cleaning/tightening all my connections and I have not had an issue since. I was ready to buy all new battery and solenoid cables, but I have not had a no click, no start issue since I took care of the connections.

 

 

The starter.. Have someone hold the key to start while you gently tap the starter.

 

 

If you have some sort of performance chip, which basically all 7.3s do, you need to pull it first. I had this issue once when my chip (which I didn't even realize I had yet) was loose.

 

A "performance chip" cannot cause a "No starter engagement" issue on this truck. The starter circuit doesn't go anywhere near the PCM.

If batteries or their cables were at issue, then there would be a noticeable change in something else like lights dimming or going out when the starter attempts to engage. This was not reported.
Auto or manual transmission (the interlocks are different)?

Have you checked to see if the starter relay in the CJB "clicks" when the key is turned to START but the circuit fails?

 

 

That narrows things considerably. You're now down to a fuse, the starter relay, the starter motor, or the associated wiring and connections.

1. Verify fuse F61 under the dash is not blown and is actually passing power (ALWAYS HOT).
2. Swap the starter relay for an identical noncritical relay.
3. Check for the application of battery voltage at the small terminal of the starter (in START).
4. Verify that the large cable at the starter is intact and is supplying battery voltage (in START).

If you get through all of that and everything checks out, it's the starter motor itself. You might want to crawl under there and do a visual of the connections as they've been known to rot off.

 

Update to problem complete with fix: Decided to take starter off to really make sure was getting good case ground and such. The entire starter was caked with oil and dirt as is pretty typical with these old trucks. While taking starter off the heat cycle hardened solenoid plastic cracked and broke. This was not a bad thing though as when got starter out from under truck saw what appears to have been the problem. Should have known as have had the exact same problem on a tractor several times before: For a while there I was on this kick where I put star washers under any bolt or connector in order to (in theory) keep better connections during corrosive events, etc. The problem was that due to some corrosion as well as (I suspect) the cable being slightly too loose this thin washer was overheating and had the distinctive look of arcing all over it. If you have ever seen this you know what I am talking about. Swapped a new solenoid on starter, made sure all connections where clean and free of corrosion when reassembled and have not had a hesitation since. Thanks again to everyone who replied to this thread, you are much appreciated.

 

Thank you for closing the loop on your thread. Glad you solved it.
The number one first thing to check(as you now know) is the grounds, especially on anything 5+ years old.
Another quick sure fire way to zero in on something like this is a voltage-drop test. It will find the weak link every time.