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Pete
Pete, Auto Service Technician
Category: Chevy
Satisfied Customers: 24654
Experience:  14 years GM dealer Technician.
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We have a 2012 chevy express 3500 6.6 duramax van with a

Customer Question

We have a 2012 chevy express 3500 6.6 duramax van with a crank no start. Scanned for codes found no codes. The vehicle was running and shut off. Will not restart. We have good reading for the crank  and cam sensor. any ideas?

Submitted: 1 year ago.
Category: Chevy
Expert:  Pete replied 1 year ago.
My name is ***** ***** I am a professional here at Just Answer. I noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.
I have seen in some cases where a completely restricted fuel filter can cause this here.If this has not been checked or replaced I would see if this is the cause.If this was already checked or replaced or is not the cause here let me know.
Thanks Pete
Expert:  Pete replied 1 year ago.
Hi,
I am following up with you to see if you still needed help with your question you had asked.If my help didn't satisfy your question please let me know so we can continue.
Thanks Pete
Customer: replied 1 year ago.

Ok. We'll check that.

Customer: replied 1 year ago.

Ok, we've checked the filters. We don't have any rail pressure. How do you check the injector pump.

Expert:  Pete replied 1 year ago.
Was anything done on the vehicle recently that may have caused this issue at all before the fault occurred?
Customer: replied 1 year ago.

No other than an oil change nothing previous

Expert:  Pete replied 1 year ago.
Below is the procedure I have located for the high side fuel injection pump diagnosis,I hope this helps you to locate the fault and to see if the pump is faulty.
Circuit/System Description
The high pressure fuel pump is located at the front of the engine valley and is engine driven by the camshaft gear. Fuel is drawn by the fuel supply pump from the primary fuel tank and delivered through the diesel fuel conditioning module to the high pressure pump. The engine control module (ECM) controls the fuel rail pressure using two pulse width modulated fuel rail pressure regulators. Fuel pressure regulator 1 is located on the fuel injection pump and meters the amount of fuel that enters the high pressure side of the pump. From the high pressure pump, the fuel moves to the two fuel rails through a high pressure metal line. The fuel rails distributes high pressure fuel to all 8 fuel injectors. The ECM varies the pulse width modulated voltage to the fuel pressure regulator 2 to relieve excessive fuel pressure which returns to the fuel tank. When the ignition is OFF, fuel pressure regulator 2 opens to bleed off the pressure in the fuel rail.
The ECM commands fuel pressure regulator 2 to control fuel pressure at idle and commands fuel pressure regulator 1 to control fuel pressure when engine speeds are above 1700 RPM. Under certain conditions both regulators are used to control fuel pressure. The actual and desired fuel pressures should be within 690 kPa (100 psi) during all engine operating modes.
Diagnostic Aids
* Contaminated fuel or incorrect fuel may cause erratic fuel pressure.
* A low fuel condition may cause driveability concerns.
* Water or contaminated fuel may cause driveability concerns. Refer to Contaminants-in-Fuel Diagnosis
* When ambient temperatures are below 0°C (32°F), the fuel tank pickup screen may be iced over from water in the fuel tank.
* High fuel injector return flow may cause fuel pressure control concerns.
* The addition of fuel system enhancements, such as auxiliary fuel tanks or add on fuel filters may relate to driveability complaints.
Special Tools
* CH-48027 Digital Pressure Gauge
* CH-50375 Fuel Injector Return Line Adaptor
* CH-50377-A Fuel Injector Return Line Plug
Circuit/System Verification
Note:
* If you were not referred to this test from another diagnostic, do not perform this procedure.
* Only perform this test when the fuel temperature is warmer than 18°C (65°F).
Engine cranking, observe that the Actual Fuel Rail Pressure and the Desired Fuel Rail Pressure are within 690 kPa (100 psi).
Circuit/System Testing
1. Ignition OFF, verify there are no external leaks or damage to the fuel return and supply lines.
◊If a condition is found, refer to Fuel Leak Diagnosis
2. Install the CH-48027 to the fuel rail service port. Engine cranking or idling, verify that the CH-48027 displays between 1-6 in Hg vacuum.
◊If greater than the specified range, inspect for a restricted fuel filter, kinked, or restricted fuel supply lines. Refer to Fuel System Diagnosis
3. Install the CH-50375 with a gauge to a fuel injector return line.
4. Engine cranking or idling, verify the injector return line pressure is greater than 3 bar (43 psi).
◊If less then the specified range, refer to Fuel Return System Diagnosis
5. Remove the fuel pressure regulator 2 return hose and plug the hose to prevent fuel leakage.
6. Install a section of rubber fuel hose on the fuel pressure regulator 2 outlet and place the loose end of hose into a clean fuel container.
7. Perform the applicable test listed below:
Cranking Test - Engine No Start
1. Engine cranking for 15 seconds.
2. Observe the volume of fuel from fuel pressure regulator 2. The volume of fuel should be less than 10 ml (0.4 oz).
◊If greater than the specified value, replace the Q45B fuel pressure regulator 2.
Note:
* Perform Steps 7.3 - 7.4 on each injector.
* Complete Steps 7.3-7.4 on all the fuel injectors before performing any repairs.
3. Disconnect the electrical connector and the fuel return line from one of the fuel injectors. Install the CH-50377-A to the return line to prevent leakage.
4. Engine Cranking for 15 seconds, verify no fuel leaks from the fuel injector.
◊If any fuel leaks from the injector, replace the fuel injector.
5. Disconnect the harness connector at the fuel pressure regulator 2 and crank the engine for 15 second.
6. Verify a steady flow of fuel comes out of the fuel pressure regulator 2 outlet.
◊If no return volume, replace the G18 high pressure fuel pump.
Engine Running Test - Engine Starts
Note:
Measure only the amount of fuel that leaks after the engine has reached 1800 RPM.
1. Engine idling, increase engine speed to 1800 RPM for 15 seconds.
2. Observe the volume of fuel from fuel pressure regulator 2. The volume of fuel should be less than 10 ml (0.4 oz).
◊If greater than the specified value, replace the Q45B fuel pressure regulator 2.
8. Install the fuel pressure regulator 2 return line.
Note:
* This procedure must be performed at idle and at 1800 RPM.
* When commanding fuel rail pressure at idle the maximum achievable pressure will be approximately 120 MPa (17404 psi).
9. Command the fuel pressure incrementally through the entire fuel pressure range with a scan tool. The Actual Fuel Rail Pressure and the Desired Fuel Rail Pressure should be within 690 kPa (100 psi) for the entire fuel pressure range.
◊If the desired and actual fuel pressure at idle is within 690 kPa (100 psi) and was not within 690 kPa (100 psi) at 1800 RPM, replace the Q45A fuel pressure regulator 1.
◊If the desired and actual fuel pressure at idle was not within 690 kPa (100 psi) but was within 690 kPa (100 psi) at 1800 RPM, replace the Q45B fuel pressure regulator 2.
◊If the desired and actual fuel pressure was not within 690 kPa (100 psi) at idle and at 1800 RPM, replace the G18 high pressure fuel pump.
10. If all the components test normal, test the fuel injector return flow. Refer to Fuel Injector Diagnosis
Thanks Pete
Customer: replied 1 year ago.

Where is regulator 2 located

Expert:  Pete replied 1 year ago.
https://www.dropbox.com/s/rrpofihqfa51kjw/fp-07-09.gif?dl=0
1 - Fuel Pressure Regulator 1
2 - Engine Coolant Temperature (ECT) Sensor
3 - Fuel Temperature Sensor 1
4 - Fuel Pressure Regulator 2

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