All, I was pulling the horse trailer home from Kansas last Friday (to Mpls) when right in Des Moines the truck stumbled. I thought It might have been horses messing around..nope, about 30 seconds later the engine stalls on the side of I35. I ended up having everything towed, truck on a rollback, trailer via an tow company employee pickup. I had the truck delivered to the local Ford dealer, and they weren't going to be able to look at it until Monday.

I made a few phone calls and the bride posted to FB and I secured a ride for the horse trailer from Des Moines to a friends farm in Clear Lake IA. The another friend came to Clear Lake with a car trailer, we went to the dealer and winched the truck up and brought it to Clear Lake, un hooked, grabbed the horse trailer and got all the animals home on Saturday. Sunday I went back to Clear Lake and got the truck.

It's in the garage at home now. I pulled the codes and got a P0340...CPS error. I swapped that with a known good spare. Here's the interesting part though. While on the side of the road, I tired to start it numerous times...fiddled with the CPS wiring, tired to start. Fiddled with the Hydra connection, tried to start..nope. The out of nowhere, it would not spin the starter. I can hear a clunk of the solenoid driving the Bendix to the flexplate. That's really why I didn't try to swap the CPS out on the side of the road.

I clean the top side battery terminals...no change. So at his point I'm thinking the starter mounted solenoid has left the chat.

Thoughts? and thanks for picking up my call @FordTruckNoob

 

I think the starter going out was just coincidental to your CPS failure. How old is the starter? Did hammering on it do anything for it? Have you removed it yet? If so, did you hear the solenoid retract as you removed it?

I am sorry for your troubles Dan.

 

I can always hear it fire the Bendix out. I go underneath with a socket and rotate the crank....no change.

The starter was a 19k mile, in 2023, 6.7L starter that I put a 7.3 nose cone on. If the mileage was true it can't have 30k miles on it. The darndest thing is, I can't seem to source a starter solenoid for it. So I order another 6.7 starter. I have a spare 7.3 three bolt starter, but I'm not going through the effort to install it as I really like the 6.7 starter.

I keep a spare CPS and the tools to change it, and would have on the side of the road....if not for the starter issue.

 

Hmm, so the solenoid is fine as far as extending and retracting the gear goes. Is it connecting power to the motor?

 

I'll check that connection tonite.

 

Simple test have someone turn the key and when you hear the clunk hit the starter with a hammer. If it works it's most likely in the brushes/armature.Of course this is assuming all of the electrical connections are brite and tight and you have the proper voltage.

 

That sounds a lot like my CPS failure 18 months ago while we were 600 miles away. Also, I'm with Leonard in thinking that it is a coincidence.

My CPS failure was somewhat intermittent.

Sometimes the truck would not start, only crank.
Sometimes the truck would start and run for a few seconds.
Sometimes the truck would start and run for a minute or several.
Sometimes the truck would start and run for hours going down the road.

 

Your end scenario could be low voltage from weak batteries.

How does she respond to new CPS?

 

I put my booster charger on it. Made sure that the batteries were up, no change.

Here's the thing, I didn't crank and crank and crank. I can tell if it's going to start or not. And I really sensed no loss of cranking rpm prior to the starter giving up. I have no idea on how it responded to the new CPS as I haven't been able to start it.

@Sous Over the last few weeks I had noticed a rhythmic rolling idle, different than the super smooth idle I had become accustomed to. I feel, now, that was an indicator of things to come.

I have a new starter coming today, I'll know more tonight.

edit: I see that RiffRaff offers a house branded CPS claiming it acts better than the OEM black CPS. It's $80 but out of stock. As another info point, the CPS I took out was a black CPS I had installed some time ago.

 

I would pull the Hydra and see what happens if a new CPS didn't help.

 

@FordTruckNoob @Sous and any others

I have the starter turning the engine over now. Looking for what parameters I should look for on my scan tool (AE) to diagnose the no start. As it stands right now, I have zero ICP when cranking. I'm going to check for fuel flow and cranking rpm, but would like the handy list.

Edit: I looked at three data
Cranking rpm = 200
IPR duty cycle = 64%
ICP - this would fluctuate between 0 and 12 psi. Unplugging I would see 2400 or whatever the default is.

I tested the ICP harness, I'm confident that everything is fine with that.

And the fuel pump is running. I have yet to put a gauge on that though.

 

Based on this low ICP, with commanded IPR very high, and no start with ICP unplugged - it appears the IPR valve is not closing enough to build pressure. Combined with the rolling idle and engine stall with no immediate restart, I'd change the IPR next. I'd suggest resealing it, but since it stalled on you, the coil might be intermittent, so I'd change the whole thing.

 

What did you do to get it cranking over again?

 

I'm not saying you're wrong, but the IPR is maybe 3 years old. Brand spanking new Motorcraft from RiffRaff.

The HPOP is relatively new, CNC Fab Stage 2...can these just straight up fail? I thought they get weak before they fail.

 

Snugged up the battery cable connection at the starter.