Ok guys, it's back. Same problem from this thread:

https://www.ford-trucks.com/forums/9...lp-needed.html

In case you don't want to read through the thread, here's the summary:

Truck cranks and won't start. As I crank, I get smoke, indicating that it's firing fuel. I have hooked up AE and datalogged as I cranked for an extended period. No codes pop up. I have tracked RPM's, ICP pressure/voltage/duty cycle, injector pulsewidth, mass fuel desired, and vehicle voltage. Everything is normal. Engine RPM's when cranking are just under 200, battery voltage holds at 11 volts while cranking. ICP pressure rises quickly as it should. Injector pulsewidth and mass fuel desired rises, showing that it's firing fuel.

I have run diagnostics from AE (Buzz and KOEO). Both tests pass with flying colors.

I have jumpered the glow plug relay using a screwdriver. Still no start. Glow plugs were replaced a few months ago, GPR was replaced a few weeks ago.

It's not the CPS, because it's firing fuel.

It's not a fueling problem. I have a fuel filter in good shape, plenty of fuel, and good pressure holding rock solid at 65 psi.

HPOP reservoir is full, oil level is good.

I took Cody's suggestion to remove power from the PCM. On Monday when I did it, the truck fired up. Today, it didn't. I first pulled the fuse for the PCM keep alive, put it in and tried to start. Then I disconnected the batteries, reconnected and tried to start. Then I pulled the PCM, reconnected and tried to start. None of those worked.

It's not the chip, I've tried starting with the chip unplugged.

It shouldn't be a glow plug issue at all. On Monday the temps were 80 degrees when I tried to start. At those temps, I should be able to unplug the GPR and the truck should still start.

Fuses check out fine, I've already gone through them. EOT sensor is good. Air filter is clean. Batteries are less than a year old... Duralast gold tops. My WTS light comes on and functions normally. Starter is less than a year old, and spins very very very strong.

Monday after trying Cody's suggestion, the truck started. I drove around Monday and the truck ran perfectly fine. Yesterday I drove the truck again. The first time it cranked, it did start funny.... kind of a rough idle and some white smoke for about 20 seconds. However, it did clear up and ran fine the rest of the day.

Now today.... it just cranks and cranks and cranks and cranks.

The truck went on a 3500+ mile road trip, and started every single day. However, that rough start that happened yesterday... I remember that it did happen TWICE during the road trip. Two mornings in a row my truck started up and ran funny for the first 20 seconds, blowing lots of white smoke. Then it cleared up and ran fine for the rest of the day.

Ok guys, I'm at my wits end here. I really am. I've covered just about everything I can think of. Something is going on, and I can't figure it out. I mean, the truck is fueling while cranking. It's warm enough to NOT need glow plugs at all. HEEEEEEEEEEELLLLLLLLLLLLLPPPPPPPPPPP!!!!!!!!!

 

From the sounds of it I would try a different PCM. Removing power then trying it again does reset it, BUT.... if there is something wrong, it can return with use or finally just kill it. Mine is an early 99 otherwise I would think to try a PCM frmo a known working PSD of the same year to see if it works with that one.

 

i was thinking along the same lines as Billybob, maybe the hundreds of times the chip has been in and out has worn down the contacts or finally cracked the pcm casing or broken a solder somewhere?

 

Tow or push truck to a discrete spot with lots of wide open space.
Drain fuel bowl onto a rag.
Insert fuel soaked rag into fuel tank fill spout.
Light rag.
Retreat to a safe observable spot.
Enjoy the show.

PCM swap isn't a bad idea, but nothing is indicating that there is a problem with the PCM. You have some seriously bad juju my friend, who have you pissed off lately?

 

Curtis, you have all of the required components for combustion. I had a similar issue with my OTPSD (other than PSD) earlier this year. In that case, the timing belt tensioner had broken allowing the timing belt to slip. Now obviously this isn't your issue. However, it absolutely sounds like it's off timing. So check/change those things related to timing. CPS, PCM, IDM.

 

It doesn't seem to be a PCM problem to me. Basically once it starts, it runs perfectly. I would think that with a bad PCM, it would also have problems running, not just starting.

But I don't know for certain. I keep leaning towards some sensor or something in the engine causing a problem, but there very well could be something wrong with the PCM... it just doesn't act like it once it's up and running.

Don't tempt me. I'm half a second away from doing that very thing.

Well unfortunately I don't have anything handy to actually check injection timing (such as an oscilloscope).

 

Just for something to check, have you looked at the wiring harness on the driver's side valve cover? The vibration of the motor has been known to wear through the insulation on the wires and cause hard to diagnose problems.

 

Yep, those have been completely checked through. Also they are snug under the valve covers, and have the clips to keep them from popping out. I also ran a buzz with all 8 injectors buzzing strong, and I don't get a P1316 code.

 

The only reason I leans towards the PCM is that with electronics, being that they are made of different metals and plastic, do generate some heat even if very little with power running through them. Once reset, it has basically cooled. When running, heat can cause some of the metals in the components to expand or contract. With old and/or worn components, as they are used they do tend to lose their "tolerance" and lose their "functionality".

That and swapping PCMs is an easy test.

 

If you happen to have a spare that is.

 

Yeah I don't have a spare PCM.

Someone over at PSN had an issue where their truck did the same thing as mine. Random no-starts or hard starts, smoke while cranking, etc. They replaced the CPS and it fixed it.

I don't know if that's the issue, but I have spares. So I'm going to start knocking out the easy stuff first, swap the CPS to see if it starts. After that, I may unplug the ICP sensor. If that doesn't work, I'll try the block heater just as a test and to eliminate any possibility of it being solely related to cold start glow plug issues. After all, my hard starting only happens after the truck has been sitting at least overnight. Once warmed up, I have had zero problems starting.

 

Well just great, truck is running again. For how long? I have no clue.

Monday it started right up after disconnecting and reconnecting the batteries.

Today I went to swap out the CPS, only to find the bolt holding it in is frozen solid in place. After lots of penetrating lube and cussing, I couldn't budge it at all, and was afraid of stripping it out.

So after giving up on the CPS, I decided to unplug the ICP sensor and crank. Lo and behold, it started right up without missing a beat. So I killed the engine after a few seconds, plugged the ICP sensor back in, and again the truck started right up and ran flawlessly.

I guess I'll have to wait and see if it doesn't crank again, and try the ICP sensor thing a second time and see if I get the same result. I'm not yet convinced that's the problem.

 

I assume you are getting closer to the problem then???

Sorry, nothing more to add.

 

Sorry that my earlier suggestion wasn't a cure for your problem.

I sure hope that the truck acts up enough to find the problem. Few things are more frustrating than trying to diagnose an intermittent condition.

 

Thats about all I have to say at this point...