The truck had the head gaskets replaced and a new turbo installed about two years ago. However, over the last month, I have noticed it “surging” and lacking power at wide open throttle (WOT).
I used the Torque Pro app to monitor the fuel pressure. At WOT, the pressure starts around 23,000 psi, but when the power drops and the surging occurs, it falls to between 10,000 and 13,000 psi.
The mechanic suggested that the turbo might be dirty and needs cleaning due to infrequent use. However, I am starting to think the fuel pump might be failing. Does anyone have other insights?
Spread pins are a typical feature of harnesses. On 6.4’s, pumps don’t break down. Under the valve cover on the right side, install a new injector harness and fuel pressure sensor.
I recommend changing the fuel filters as soon as possible to see if that resolves the issue. When I first got my 6.4, I experienced something similar. If you have changed them recently, it might be due to dirty fuel, so it would be a good idea to replace them again.
I would check the fuel pressure for the HFCM (low-pressure pump) before it reaches the fuel cooler. Make sure you are getting between 3-8 psi. You will need to disconnect the line and find a way to rig a gauge to it. I usually use a fuel pressure gauge from Harbor Freight.
Thank you. I am having a hard time believing the mechanic when they say, “turbo dirty,” especially since the boost is smooth and the fuel pressure is dropping.