wont start please help
-check HPOP res, oil should be within 1" of the top, if low you could be getting air in the oil lines that fire the injectors.
-needs to crank at least 100rpm for the electronics to activate.
...just a few to start.
Search "cold start" and read through the threads, theres plenty of great info to help.
Theres a cold start thread specifically for no starts in cold weather.
OT, do you have to pull the HPOP res to change the HPOP seals? If so can you check out my "pulling HPOP res...." thread and give me some input if you can.
-Al
What I will show you is a rough draft of the sheet that the technician’s use to go by when they have a hard start / no start concern. This sheet has to be filled out under a warranty claim or will be kicked back to the dealer. I’m going to add some of my comments to each one. So sit back and enjoy the ride, that is if you get your truck started. They have changed the order of the steps as the years went on but the sheet is basically the same from 94 1/2 to 01.
#1 Visual engine/Chassis Inspection
Fuel,Oil,Coolant,Electrical
Comment: Just a basic check over for anything out of the ordinary.
#2 Check Engine Oil Level
Contaminants,Correct grade / Viscosity/ Miles / hours on Oil,Correct level,level in High Pressure Pump reservoir
Comments: This has got to be the most over looked problem on the powerstroke. I have seen technician’s spend hour after hour looking for a problem, just to find it was low on oil.
#3 Intake/Exhaust Restriction
Inspect air filter /ducts-exhaust system and back pressure valve.
Comments: I have seen a lot of squished tail pipes on buses. The air cleanerhousing has a filter minder (restriction gauge) on it. A plugged air filter could cause a lot of problems. I have also seen the back pressure valve come on uncommanded. What caused this you asked, the back pressure regulator was bad.
#4 Sufficient Clean fuel
Check fuel tanks/Drain sample from fuel filter while cranking. If possible ask customer if the water in fuel or fuel filter (restriction) lamp has come on.
Comments: If there is anything a powerstroke hates it’s water. If there is a lot of water in the fuel filter housing it could corrode the heater apart and end up by shorting out on the housing causing a fuse to blow. If that happens you could have a no start condition. If you are trying to drain the fuel filter housing and nothing is coming out, you could crack open the cover a little or crank the engine over, it doesn’t need to start.
#5 Tandem Fuel Pump Pressure
Measure fuel pressure at the shrader valve located on the regulator block. It must have a minimum of 100 RPM cranking speed for 20 seconds and if it has dual tanks it should be checked on both tanks.
Comments: If the pressure is below cranking spec the fuel filter should be replaced first and retest.
#6 Perform KOEO On Demand Test
Use The NGS Tester to check for codes.A pass Code is P1111
Comments: NGS stands for (New Generation Star) tester. KOEO stands for (Key on Engine off). This test is used to determine if the PCM (Powertrain Control module) has detected any fault conditions. If a fault is detected a diagnostic trouble code should be set.
#7 Retrieve Continuous Trouble Codes
Diagnostic Codes retrieved during this test are historical faults. Pass Code P1111.
Comments: The purpose of this is to determine if the PCM has detected any historical or intermittent fault conditions. The condition that caused a continuous code may no longer exist. In this test function there is a button to clear codes. This will clear all the codes unless its a hard fault (meaning happening right now) code. I have seen tech’s clear the codes in the Continuous mode and then check for codes in the other mode’s not knowing that they cleared them.
#8 KOEO Injector Electrical Self Test
Use the NGS tester. Pass Code P1111. All injectors will momentarily buzz, then individual injectors will buzz in sequence 1 through 8. Diagnostic codes will be transmitted after the test is completed.
Comments: The test will not always pick up a weak injector. What I do is listen to the sounds of the buzzing, usually a problem injector sounds quieter than the rest.
#9 NGS Tool- Data List Monitoring
NGS tester may reset below 9.5 volts. Select the parameters indicated from the NGS parameter list and monitor while cranking. The pid’s are V PWR (vehicle power ) meaning batteries. RPM (revolutions per minute). ICP ( injection control pressure) and FUEL PW (pulse width). V PWR - Cranking spec is 7 volt minimum. If V PWR indicates low voltage, check battery volt, charging system or power. Circuits grounds to PCM.
RPM- low RPM could be an indication of starting/charging system problems. No RPM indicated with the engine cranking- could be CMP circuit fault, check for diagnostic trouble codes.
ICP- a minimum of 500 PSI(3.4 mpa) is required before the injectors are enabled. No or low oil in the reservoir, system leakage, faulty IPR or high pressure pump could cause pressure loss.
NOTE: CMP signal is required before ICP pressure is allowed above 800 PSI.
FUEL PW- No fuel demand command signal(0 ms ) when ICP, RPM and V PWR signals are correct usually indicated loss of CMP sync signal.(Check for trouble codes and check CMP circuit)
Comments: Obviously without an NGS tester you won’t be able to perform these checks, but this is a quick way for a technician to see what circuit is having the problem. The CMP ( camshaft position sensor) is located in the front cover of the engine and is one of the sensors that causes the most problems. The CMP sensor is a hall effect sensor used to indicate engine speed and camshaft position. They have also been through a lot of upgrades since the engine first came out.
#10 Glow Plug System Operation
Check voltage between the glow plug relay terminal with the single black/red wire and battery ground. If no voltage present, repair open in supply circuit(two fusible link wires connected to starter relay). Check voltage between the glow plug relay terminal with the two brown wires and battery ground. Turn key to the run position, measure ‘ON’ time. Verify sufficient glow plug ‘ON’ time. If no voltage present, replace glow plug relay. 9-12 volts relay on time the spec is 10 to 120 seconds. NOTE: Wait to Start Lamp ‘ON’ time is Independent from Glow Plug Relay ‘ON’ time.
Glow Plug Operation: Measure Glow Plug Resistance to Batt. Ground, Remove all glow plug/injector connectors and measure GP Harness Resistance to Relay. Spec for glow plug to ground is .1 to 2 ohms. Spec for connector to relay is 0 to 1 ohms.
Comments: Nine out of ten times the glow plug relay is the cause of a hard start and I believe it should be checked second behind checking the oil on the check list. The latest hard start sheets move this test up depending on engine temperature. When checking for a glow plug problem pay careful attention to the harness end and connectors for burnt wires.
Dave / Believer45




