Thanks for the replies. A special thanks to Ethan1 and Trav, both your suggestion were helpful. I have not yet managed to fix the truck unfortunately.
What I have done:
Pulled the COP and used a jumper cable and spark plug to verify it does have spark.
Used a compression tester and got 120 PSI with a cold, dry engine. When I was doing the test I neglected to open the throttle, nor did I add oil to do a wet test. Well, I am a rookie...so this didn't really tell me much.
Connected a light to the fuel injector connector. It flashed as the engine ran.
Installed Forscan on my computer. This truck has MANY problems:
===PCM DTC P0307===
Code: P0307 - Cylinder #7 Misfire Detected
Module: Powertrain Control Module
Diagnostic Trouble Code details
Cylinder #7 Misfire Detected
Ignition System
Fuel System
This DTC may be caused by :
Blocked kinked or crushed fuel lines
Fuel contaminated
Evaporative emission control system malfunction
EGR system fault.
Base engine fault
Check for any other codes that may cause a misfire.
===END PCM DTC P0307===
===RCM DTC B1884===
Code: B1884 - Passenger Air Bag Disable Warning Lamp Circuit Failure
Module: Restraint Control Module
Diagnostic Trouble Code details
Passenger Air Bag Disable Warning Lamp Circuit Failure
--- Possible Causes --------
-PAD Warning Lamp Inoperative
-Suspect
-Warning Lamp -Electronic Crash Sensor (ECS) Module
Suspect a short in the wiring.
===END RCM DTC B1884===
===RCM DTC B1318===
Code: B1318 - Battery voltage Low
Module: Restraint Control Module
Diagnostic Trouble Code details
Battery Voltage Too Low
--- Possible Causes --------
- Battery Voltage below 9.6volts
-Suspect Battery state of charge Charging system
===END RCM DTC B1318===
===GEM DTC B1365===
Code: B1365 - Ignition start circuit battery short
Module: Generic Electronic Module
Diagnostic Trouble Code details
Ignition start circuit battery short
===END GEM DTC B1365===
===GEM DTC B1431===
Code: B1431 - Wiper Brake/Run Relay circuit failure
Module: Generic Electronic Module
Diagnostic Trouble Code details
Wiper Brake/Run Relay circuit failure
--- Possible Causes --------
This code can be generated by:
-Ground/Short Front Wiper RUN/PARK Relay
-Open/Front Wiper RUN/PARK Relay
-Suspect Front Wiper RUN/PARK Relay
-Suspect Generic Electronic Module
===END GEM DTC B1431===
===GEM DTC B1434===
Code: B1434 - Wiper speed relay coil circuit failure
Module: Generic Electronic Module
Diagnostic Trouble Code details
Wiper speed relay coil circuit failure
===END GEM DTC B1434===
===GEM DTC B1458===
Code: B1458 - Wiper washer pump motor relay coil circuit failure
Module: Generic Electronic Module
Diagnostic Trouble Code details
Wiper washer pump motor relay coil circuit failure
===END GEM DTC B1458===
===GEM DTC B1840===
Code: B1840 - Wiper Front Power Circuit Failure
Module: Generic Electronic Module
Diagnostic Trouble Code details
Wiper Front Power Circuit Failure
--- Possible Causes --------
This DTC can be generated by:
-Ground Short Front Wiper Power Feed
-Open Front Wiper Power Feed
-Suspect Generic Electronic Module
===END GEM DTC B1840===
===GEM DTC B1428===
Code: B1428 - Safety belt lamp circuit failure
Module: Generic Electronic Module
Diagnostic Trouble Code details
Safety belt lamp circuit failure
--- Possible Causes --------
This code can be generated by:
-Ground Short Driver's Seat Belt Lamp
-Open Driver's Seat Belt Lamp
-Suspect Driver's Seat Belt Lamp
-Suspect Generic Electronic Module
===END GEM DTC B1428===
===GEM DTC P0500===
Code: P0500 - VSS sensor circuit fault.
Module: Generic Electronic Module
Diagnostic Trouble Code details
VSS sensor circuit fault.
Open VSS circuit.
Shorted VSS circuit.
This DTC may be caused by :
Suspect VSS.
Worn or Damaged VSS drive gear on transmission output shaft.
Suspect PCM.
Faulty or damaged instrument cluster module.
===END GEM DTC P0500===
===GEM DTC B1318===
Code: B1318 - Battery voltage Low
Module: Generic Electronic Module
Diagnostic Trouble Code details
Battery Voltage Too Low
--- Possible Causes --------
- Battery Voltage below 9.6volts
-Suspect Battery state of charge Charging system
===END GEM DTC B1318===
===GEM DTC B1315===
Code: B1315 - Battery saver relay coil battery short
Module: Generic Electronic Module
===END GEM DTC B1315===
===RAP DTC None===
Successful DTC reading, no error codes found
Module: Remote Anti-Theft / Personality Module
===END RAP DTC None===
===ABS DTC None===
Successful DTC reading, no error codes found
Module: Antilock braking system
===END ABS DTC None===
I have the truck connected to a battery charger at this time. It may be low from cranking and not starting, or starting for a few seconds and being shut off.
I would really like to help my son in law, he's a good guy. But this is beyond my ability.