My 2003 Duramax LB7 is one of those that has the starting problem when it is hot. Starts fine when cold. Won't start when hot. Runs great, smooth, no smoke, when it starts. Dealer says injectors test ok.
I have done the following:
Put an Air Dog lift pump on and removed the stock fuel filter head and replaced the fuel hoses.
Shimmed the fuel pressure regulator valve.
I have found a way to start it when it is hot which will sound bizarre but it works every time. Put a bag of ice cubes on top of the engine where the thermostat head is and wait 15 minutes and it will start. Not kidding. It works.
My question is what might be located in the general are of the thermostat cover that would keep the engine from starting when it is hot and be effected by cold water enough that it would then allow the engine to start when it is cold.
Any ideas out there.
The only thing I can think of is the Fuel Pressure Regulator.
Thank you for any help.
I have done the following:
Put an Air Dog lift pump on and removed the stock fuel filter head and replaced the fuel hoses.
Shimmed the fuel pressure regulator valve.
I have found a way to start it when it is hot which will sound bizarre but it works every time. Put a bag of ice cubes on top of the engine where the thermostat head is and wait 15 minutes and it will start. Not kidding. It works.
My question is what might be located in the general are of the thermostat cover that would keep the engine from starting when it is hot and be effected by cold water enough that it would then allow the engine to start when it is cold.
Any ideas out there.
The only thing I can think of is the Fuel Pressure Regulator.
Thank you for any help.
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