[wastefarmer]

Have 03 GMC 2500hd Duramax 107k miles. Crank no start. Removed factory fiuel filter and pump. Installed FASS lift pump and filters. Shows only 500 lb. Fuel pressure at cranking. Will start with either and runs fine.

Have replaced: Truck cranks but won't start. Fuel pressure is only 500 lb during cranking but it's fine once it starts. I have replaced CP3, fuel pressure regulator, fuel pressure sensor and fuel pressure relief valve. Have done injector return test all injectors in specs but the CP3 was out of space so that's why I replaced the CP3. Installed fass system and remove the stock fuel filter housing and filter. Fuel pressure while starting is only 500 lb. Once the truck starts it runs like a champ. Balance rates perfect. Have removed valve covers and performed fuel return rates on all injectors, all in spec CP3 was out if spec on return rate and replaced. No smoking no hazing. Your thoughts.



Have also done all the below:

1. Fuel pressure relief valve with oem

2. CP3 with Reman with new fuel pressure regulator from Diesel Logic

3. Fuel pressure sensor replaced.

 

[Ron Nielson]

You're done everything you need to do except for ...... Hmmmm can't come up with anything.
Read this and see if there is anything that might help you. Chevrolet-GMC Diesel Diagnostics You might even call Oregon Fuel Injection or Lincoln Diesel Specialties. Phone numbers for both easy to find by looking on Google.Both are very helpful..

Of course the 500 lb pressure cranking is the problem. Can't fugure out why you are at 500.