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Discussion Starter · #1 ·
I recently bought this truck from the auction 2 months ago. It was fine up untill recently. I brought to a shop to get my plow put on. Dropped it off the night before and everything was fine. Get a call in the morning from the shop saying they could not get the truck started. It was cranking and cranking and noticed smoke coming out of the tailpipe. To me it seemed white/gray.

I finally get it to start and it was good for about 2 days. Before i left for vacation i got in to start it to move the truck so it wont be in the way and it would not start. I killed the batteries trying to start it. This time no smoke. So i scanned it and pulled these codes

p1125
P2122
P2128
P2133

Im scratching my head because im not understanding why all these codes would come up out of the no where.

Im thinking its electrical but i havent dug into it to trace wires and such.... Anyone else with this problem?

I also did replace the diesel cooler that sits in front of the gas tank but that was 2 weeks before it started acting up.
 

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Does it help to pump the fuel primer before you try to start it-??

Does the engine oil smell like diesel-??
 

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Discussion Starter · #3 ·
Priming does not help. Now code p0700 comes up and p0641 and p0651. Checked oil and does not smell like fuel and its not overfull.
Also noticed whenever i go to crank it my guages wont register (the dont go up) but if i cucle the ignition 2 or 3 times the gauges start moving.... Truck still wont start....
 

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Can you reset the codes? Do they return?
p1125
P2122
P2128
P2133

These are from the Accellerator Pedal Position Sensor, which is at the top of your Accellerator Pedal Bracket.
P1125 APP Sys

P2120 Throttle/Pedal Pos Sensor/Switch D Circ
P2121 Throttle/Pedal Pos Sensor/Switch D Circ Range/Perf
P2122 Throttle/Pedal Pos Sensor/Switch D Circ Low Input
P2123 Throttle/Pedal Pos Sensor/Switch D Circ High Input
P2124 Throttle/Pedal Pos Sensor/Switch D Circ Interm
P2125 Throttle/Pedal Pos Sensor/Switch E Circ
P2126 Throttle/Pedal Pos Sensor/Switch E Circ Range/Perf
P2127 Throttle/Pedal Pos Sensor/Switch E Circ Low Input
P2128 Throttle/Pedal Pos Sensor/Switch E Circ High Input
P2129 Throttle/Pedal Pos Sensor/Switch E Circ Interm
P2130 Throttle/Pedal Pos Sensor/Switch F Circ
P2131 Throttle/Pedal Pos Sensor/Switch F Circ Range Perf
P2132 Throttle/Pedal Pos Sensor/Switch F Circ Low Input
P2133 Throttle/Pedal Pos Sensor/Switch F Circ High Input
P2134 Throttle/Pedal Pos Sensor/Switch F Circ Interm
P2135 Throttle/Pedal Pos Sensor/Switch A / B Voltage Correlation
P2136 Throttle/Pedal Pos Sensor/Switch A / C Voltage Correlation
P2137 Throttle/Pedal Pos Sensor/Switch B / C Voltage Correlation
P2138 Throttle/Pedal Pos Sensor/Switch D / E Voltage Correlation
P2139 Throttle/Pedal Pos Sensor/Switch D / F Voltage Correlation
P2140 Throttle/Pedal Pos Sensor/Switch E / F Voltage Correlation


Page 6-2779 of the Manual gives a long list of possibilities that should be checked either before cranking, or during cranking. Some of these items seem a bit more like guesses, versus common sense approach. Such as:
Engine Coolant Sensor (ECT) - before cranking
Fuel Rail Pressure (FPR) - while cranking
Loose Crankshaft Position Sendor Reluctor Wheel
Defective Crankshaft Position Sensor or associated wiring
Defective Camshaft Position Sensor or associated wiring
Fuel Pressure Regulator or associated wiring
Glow Plugs or associated wiring or Controller

If you have a Bad (Crankshaft or Camshaft) Sensor, the truck won't start.

Basically you need Air, Fuel, an engine that will crank over, and the Electrical controls to do so. But, this reaches deeper into and around the engine as Sensors, Computers, Heaters, and CPU Communications between Modules must also work properly.

If I were in your shoes, I'd start with the Glow Plugs, verifying each one has the same OHM Value, followed by a good electrical connection to the Power Bus feeding them. Once those were done, I'd verify that I had 12 VDC from the Main Fuse to the Controller and a 12 VDC Pulsed Output to the Power Bus making the Glow Plugs Heat. (One thing I haven't tried yet is a No Contact Infared Heat Sensor pointed at each Glow Plugs base with the Ignition "ON" to see if that could be a Easy Valid test.) Once you know 100% that all Glow Plugs are working, I'd move on to checking the Fuel Supply to the Engine Compartment Fuel Filter and CP3.

Does your Fuel Filter Pump actually pump up the fuel pressure and get hard to pump? Is the Bleed Screw good, and sealing properly? Have you Pumped it up and then tried to Bleed the Filter assembly making sure you get a bit of Fuel from the Bleed Screw? Does the pressure Bleed off quickly after it is pumped up? Have you checked for Fuel Leaks or collapsed Fuel Lines? Could there be Water or Moisture in the Lines? Is the Truck in a Heated Garage or outside during starting?

Then I'd connect a OBD Bluetooth Dongle and use Torque Pro to get some data on the Fuel Rail Pressure and Engine Temperature etc.

That should give you enough information to eliminate several things.

Larry
 

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Discussion Starter · #6 ·
So I spent about 5 hours diagnosing today with the help of my friend.

Found all glow plugs are good, controller is good and everything relating to them is good.

Pumped fuel filter and found that fuel filter bleeds off very quick. Basically I pump the filter about 10 times until it get hard to push and then try to crank and nothing. go back and feel the pump and its soft again....

truck is outside when im trying to start it. but yesterday and today was in a heated garage....

im thinking it might be the cp3 or might have an issue with the FPR....maybe the sensor.

when im cranking it though i can smell diesel from the exhaust....like i said im not very experienced with diesels so don't know if that means anything....

im stumped...might have to get it towed to the dealer for further diag even though don't want too i need this truck running....
 

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IF you crack the bleeder does air come out when you prime it.
 

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You might have a problem with the APP or a bad Plug connection. The APP is located above the Hinge for the Accelerator Pedal. I've attached the Schematic for that
Potentiometer. It has three seperate circuits: APP Sensor 1, APP Sensor 2, APP Sensor 3.

The ECM supplies +5.0 VDC to each POT, and the Wiper of each POT goes back to
the ECM as APP Sensor 1 Signal, APP Sensor 2 Signal, APP Sensor 3 Signal.

+5 VDC is on Terminals G, D, J. Verify ALL +5 VDC's from ECM (in Wire Bundle) to a Good Ground.

OHM POT1 from G to E and note the TOTAL OHM Value across POT 1.
OHM POT2 from D to B and note the TOTAL OHM Value across POT 2.
OHM POT3 from J to A and note the TOTAL OHM Value across POT 3.
The Schematic doesn't tell what the OHM Value is for each POT.

OHM POT1 from E to F with your ANALOG Meter set on the next higher range that is
larger than POT1 TOTAL OHMS. Your Meter should smoothly increase or decrease as Accelerator Pedal is moved over the Pedals range.

Your ANALOG Meter needle shouldn't jump around, or hang in one spot, or quickly go to ZERO or INFINITY.

Repeat for POT 2
OHM POT2 from B to C

Repeat for POT 3
OHM POT3 from A to K

As small a range as the Pedal travels, the POTS are likely 500 OHMS or less, but I haven't measured them yet.

My guess is that all three should be very close to each other, and the ECM compares one to the other two, to make sure the original POT is correct. You likely have one that isn't working correctly, because of a bad connection, or broken wire, or a problem similar to that.


Larry
 

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I've removed my APP Plug, and got the OHM values for all three POTS.

APP SENSOR #1
Pin G = +5 VDC
Pin F = Wiper - Sensor 1 Signal to ECM
Pin E = Common

Pin G to Pin E = 2.97 K
Pin F to Pin E = 2.44K Idle Pedal & 3.2K FULL Pedal


APP SENSOR #2
Pin D = +5 VDC
Pin C = Wiper = Sensor 2 Signal to ECM
Pin B = Common

Pin D to Pin B = 2.77 K
Pin C to Pin B = 3.25K Idle Pedal & 2.77K FULL Pedal


APP SENSOR #3
Pin J = +5 VDC
Pin K = Wiper = Sensor 3 Signal to ECM
Pin A = Common

Pin J to Pin A = 5K
Pin K to Pin A = 6K Idle Pedal & 5.6K FULL Pedal

I know the OHM values seem strange but these were verified twice, on a working '03 Truck. I'd need to disassemble the Pot to find why they are strange.

When you are looking at the POT Plug (with MALE Pins) towards you,
the Pin layout is:

K J H G F
A B C D E

Pin H is not used.

Updated app.pdf is attached.


Also, pump the Fuel Plunger on the Engine Compartment Fuel Filter until it gets hard to pump.
Then use a 13mm socket to easily crack the Bleeder just enough, until you get fuel out of it.
Snug it easily so as to not bust the top of the Plastic bolt off. You may have to do this
more than once to bleed all the air.


Larry
 

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Discussion Starter · #14 ·
So i finally got it to run... Took off bleeder screw pumped and bubles were coming through with diesel... Put bleeder screw back on and pumped it again, unscrewed bleeder screw and bubles came out again... Put bleeder screw back on primed filter and fired up instantly... Let it sit for 2 hours go to start it and fires up but the cranks are long i would say 5-8 cranks before it actually fires up....

Come to find out codes for the app were do to low voltage from killing the batteries...

So im not sure if the long cranks are a bit normal or what?!?!?
 

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Sounds like you still might be picking up a little bit of air in the fuel lines
 

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If air keeps showing up from the bleeder screw I would think it is sucking in air somewhere. You can pressurize the fuel tank with air (5psi) and check all lines for leaks
 

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Rebuild the filter head did that on mine when it was cranking a lot to start fixed the problem.
 

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Discussion Starter · #19 ·
So i rebuilt the filter housing, replaced all glow plugs and rails (found 2 glow plugs not lighting up) and the thing still wont fire up right away... Let it sit over the weekend in a heated garage and the freaking thing took 20 cranks to start... After driving it for a while, shut it off and it takes about 8 cranks.... If i let it sit it will take about 20 cranks or so to start it and in the process you can hear the engine trying to catch but it takes litterally 20 cranks almost like its not getting fuel...

Also when i drive it for a while and then let it sit and idle i hear a popping sound from driver side valve cover area and also smell raw diesel...but there are no leaks anywhere.... This truck is driving me insane....
 

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Is truck making oil.
 
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