Hello,
I am brand new to the forum, and have no idea what I am doing!

I am attempting to use V7.5 with my AutoCal to gauge the fuel rail pressure on my 2007.5 6.6 Duramax LMM. When I try to read/record the Actual Fuel Rail Pressure, it tells me that it is "Not a valid PID". Is there a way to make it a valid PID?

I just bought the truck, it is a 2007 Kodiak C4500 with an auto transmission. It is throwing (2) different error codes. P0088 and P0381. I believe it is the P0088 that is putting it in limp mode and that is "High Fuel Rail Pressure". Hence, the reason I need to read the "Actual Fuel Rail Pressure".

If this makes no sense, I told you I have no idea what I am doing! I ordered in a PPE Fuel Pressure Relief Valve, it will be here tomorrow. If that doesn't fix it, the Fuel Rail Pressure Sensor is next (Hope I can get that locally?), and if neither of them work, I will replace the Fuel Pressure Regulator. Does this sound like the manner in which I should proceed?

Scott