Wife pulled up to the curb and the truck died and will not start.
tried a new PMD I know is good, but still no fire. It cranks fast and has been running good.
Both the optical sensor and crank sensor were replaced within the last year .
I disconnected the optical sensor wires and it now starts while cranking , but dies when the key is released back to run.

Thinking the optical sensor is at fault , but not sure. What is the next step before I start replacing parts. ?

Just did a code scan and it may be helpful.
P0215 & P1216.

 

P0215- Engine Shutoff Solenoid Malfunction
P1216- Fuel Solenoid Response Time Too Short


First. Being most thorough, perform all those most "Important Preliminary Checks."
Second. Perform an "OBD Systems Check."
Third. Perform the "Fuel System Supply Checks, paying special attention to the lift pump "flow, pressure, suction" test as well as the "Fuel (lift) Pump Relay Circuit Diagnostic"


I suspect fuel starvation, fuel restriction, lack of fuel, no fuel, aerated fuel.
Anything that could possibly, no matter how remote disturb the Optical Sensors relaxing day at the diesel spa will send the PCM scrambling (limp mode) if not crashing (without explanation, engine just shuts off like a ghost turned the ignition off).
PCM's lil known "panic mode" aka "Fuel Cutoff Mode".

Wheres your PMD... [thats sarcasm] PMD makes a good a scapegoat as any for techs inabilities to follow those mind numbing labor intensive monotonous factory approved diagnostic procedures..
If your not being thorough or just going through the motions, dont bother.... You must be excruciatingly thorough at each step as the next step ASSUMES everything is found good up to that point. Thats why you cant jump around, or simply skip to the DTC's diagnostic aids.



LINK- 6.5 DS Pump Diagnostics
snip
ENCODER (OPTICAL) SENSOR
If you have a no start condition, disconnect the encoder (optical) sensor and crank the engine for 15-20 seconds. If it starts then the problem is with the optical sensor.
The encoder sensor has to be able to see through the fuel inside the pump, if there is any aireation it can cause trouble codes to set. Dirty fuel, SVO, no fuel supply pressure (air in system) or dyed fuel can all cause a problem with the encoder sensor “reading” the windows in the cam disk. There are 8 windows in the low resolution circuit and 512 windows in the high resolution circuit. In on minute at idle the high resolution circuit needs to read about 180,000 windows, in order to not set a code."/snip


When was the last time the tank was dropped, cleaned, inspected, and the fuel strainer replaced? If unknown or been longer than a decade or couple hundred thousand miles, I suggest you start there..................



Good Luck

 

Thanks for the detailed help. Much appreciated.
I have my work cut out for me now.
I may be a few days getting thru all the steps, as I don't have a lot of time on weekdays.
I did confirm the lift pump is working and no air came out when I ran the bleeded hose into a bottle.
Now the battery's are low, so It is getting a charge and I will look further tomorrow after work.
Is the fuel solenoid a replaceable part? or is it integral to the fuel pump and can only be replaced by replacing the fuel pump?
Pete

 

After a lot of testing in places I have no Idea what they are, I am running again. It seems the problem goes back to what happened last fall . Same thing all over. I ended up finding the thread form the fall and got on track again. It seems the contacts in the PMD harness , or the optical sensor plug were at fault again. I removed the extension harness and got good Ohm reading on each wire , cleaned both ends with contact cleaner and it started up and ran. Died a minute later, and after unplugging the PMD harness and optical sensor plug ,and reinstalling it is running good, and starting up , all codes are gone too.
I need to get some Dielectric , grease and load up the plugs, and then tape everything up tight.
Glad I didn't buy and parts.

 

and the saga continues. Got the dielectric grease in the conections and the truck started fine, ran about 1 minute and dies. Check conections again, starts and runs a minute then dies, repeats several times, rain starts and here I am staying dry.

 

Sounds like an inop/faulty lift pump ie lift pump is working during START, but not after engine starts.
Next time it dies, quickly open the FFM and see if theres any fuel in it.. Also suggest putting a clear hose from FFM to injection pump inorder to thoroughly inspect for and rule out possible air leak(s)...

 

A fuel pressure gauge is always a good addition.

What year is your truck?

You can remove the plunger from the fuel shut off solenoid - they rarely go bad - but like any other part, they do go bad. On top of the injection pump. When the key is hit, there should be a thunk.

You truck will not start if the return line is plugged. As it's easy to get to coming off the front of the injection pump, it is one of the things I usually move up in the line of things I check.

 

This is a 98 Chev K 1500, I removed the shutoff and confirmed it is operating , so that one is out of the way. Lots of fuel coming from the lift pump too .
I am starting to think the new crank position sensor may be toast or the probl;em lies in the optical sensor, or PMD harness plugs. Will It run {poorly I expect} with the Crank Position Sensor disconnected to see if this is the problem?

 

Did you pull the return line from the front of the IP and run it to a container? It's a very easy check.

I usually jumper the lift pump and turn the key to run - so the plunger is open - and let some diesel pump through the IP

 

it seems fixed, ran for an hour and starts like a champ.
It would start and die after a few minutes then sit a few and start again and die. Last thing I did was clean and re-tighten the ground on the pump again . This seemed to be the answer. I will test drive it later when the wife is home to rescue me if it dies.