Truck stutters and turns itself off intermittently

[shr3dd3r 09]

The new CKP sensor did not fix the problem. What should I check in the ignition system? Can a PATS problem cause this kind of intermittent stalling? I swapped the PATS module when I did the swap so I could start it.

 

[RonD]

PATS disables the ignition but I don't think it would be intermittent, and light on dash should flash.

The PATS keys have a battery inside and need to be replaced sometimes, so maybe the key you are using is on its way out, but you should get the dash light.

How about this test, you said that after it dies it won't restart unless you turn the key off then back on.
What about getting a can of Quick Start, ether, and the next time it dies don't turn the key off, try to restart once, if it's still dead pop the hood and spray some ether into a larger vacuum line on the intake, i.e. pull off the hose for the PCV or Power booster and put it back on, you could pop the air cleaner but not sure on your setup of the MAF and ether, I doubt it would be an issue.
Then turn over engine(without turning key off), if it doesn't fire then spark is missing not fuel, if it does fire then fuel is missing not spark.


And just as a side note I did find a post about a Saturn that would die and then no start, turned out to be the CKP but only when it got warm, tested fine cold, so I have now heard of an intermittent CKP.

What's the temp like under the hood with that 5.0l in there, just wondering if something has gotten temp sensitive over time?

 

[shr3dd3r 09]

PATS disables the ignition but I don't think it would be intermittent, and light on dash should flash.

The PATS keys have a battery inside and need to be replaced sometimes, so maybe the key you are using is on its way out, but you should get the dash light.

How about this test, you said that after it dies it won't restart unless you turn the key off then back on.
What about getting a can of Quick Start, ether, and the next time it dies don't turn the key off, try to restart once, if it's still dead pop the hood and spray some ether into a larger vacuum line on the intake, i.e. pull off the hose for the PCV or Power booster and put it back on, you could pop the air cleaner but not sure on your setup of the MAF and ether, I doubt it would be an issue.
Then turn over engine(without turning key off), if it doesn't fire then spark is missing not fuel, if it does fire then fuel is missing not spark.


And just as a side note I did find a post about a Saturn that would die and then no start, turned out to be the CKP but only when it got warm, tested fine cold, so I have now heard of an intermittent CKP.

What's the temp like under the hood with that 5.0l in there, just wondering if something has gotten temp sensitive over time?

I can try that, but I really don't think it is missing fuel. I can hear the fuel pump running after it dies until I turn the key off. But even with the pump running it won't start back up until I turn the key off completely. I'll give it a whirl though.

 

[shr3dd3r 09]

It does get pretty warm under there, but the engine compartment, radiator, and fan are all identical to the donor vehicle, so I am not sure about heat being an issue.

 

[shr3dd3r 09]

I am beginning to reach the limit of what I can test on my own. I am stumped.

Fuel system is good.
Crank sensor and wiring are good.
Cam sensor and wiring are good.
Plugs and wires brand new.
O2 sensors brand new.
Fuel pump brand new.
Fuel filter brand new.
Fuel pressure regulator works as it should.

The following codes are present:

P1356
PIP signals present with engine not running. ECM detected a PIP signal with engine not running.
Possible causes: Failed pick-up coil or crank sensor. Failed ignition control module.

P1451
EVAP system canister vent solenoid circuit malfunction. Detected the canister vent solenoid signal moved outside the calibrated parameters at a specific duty cycle.
Possible causes: Failed canister vent solenoid. Open or short circuit.

I haven't checked on this yet but I will tomorrow. If that doesn't do the trick I don't know what else to do.


How would I troubleshoot the ignition system in general? Isn't the ignition control module integrated into the pcm?

I can only think that the coil packs or injector wiring could be at fault, but I would assume I would get some serious consistent misfiring if that were the case.

If I don't get this solved in the next day or so I'm going to have to take it to a dealer or someone with some diagnostic equipment. I can't afford to have this problem much longer.

 

[RonD]

I can try that, but I really don't think it is missing fuel. I can hear the fuel pump running after it dies until I turn the key off. But even with the pump running it won't start back up until I turn the key off completely. I'll give it a whirl though.

That is interesting about the fuel pump running with no CKP signal, crank not turning.

Either a stuck fuel pump relay or bad PCM.
Since the engine dies I would think PCM now, and that would explain most if not all of the other issues.

Occam's razor, when you have two(or more) competing theories that make exactly the same predictions, the simpler one is the better.

PCM being at fault is the simpler explanation for random failing ignition and fuel systems.

Issue with new PCM is the PATS needs to be dealt with, there is a scan tool that downloads info from existing PCM and then after you swap it you upload that info to the new PCM, so existing PATS keys work.
Most locksmiths also can program new keys into the PCM via the OBDII port, but you either have to have them come to you or do the swap at their location.

 

[shr3dd3r 09]

After replacing the cam sensor, ckp sensor, fuel pump, and fuel filter, I think my problem might be the pressure regulator (or fuel rail pulse damper) located on the fuel rail behind the intake. I have noticed my truck smoking black smoke more often now, and the intermittent stalling is still an issue.

I think it is flooding itself with fuel constantly, and occasionally it gets too much to handle and dies. It is probably pulling fuel through the vacuum hose on top of the pressure regulator directly into the intake, which is probably causing my hard starting problem as well. If this doesn't fix my problem, I'll be taking it in to Ford.

So, how does one replace this regulator? Does it just unscrew or what? I can't see how it comes off. It is in a place that is somewhat reachable but I can't really see how to remove it.