Was wondering what the different fuel pumps are in my 2005 CR and what their purpose is! I've heard of a few different things, lift pump, injector pump, the Common Rail itself, But I'm still trying to figure out where each one is in the fuel flow and when you may need an upgrade to one of them! Basically need a simple introduction to How Fuel goes from the tank to the injectors! Thanks!

 

I believe you have the same setup as my 06 5.9. Starting from the tank there is a fuel pump inside that lifts the fuel through the line to the motor. Once under the hood is enters the fuel filter housing. After being filtered it flows to the CP3. The CP3 is the brains of the system and communicates with the computer on how much fuel to send the the rail. The rail is the final spot before being fed through the individual fuel line to the connector tube which dumps it in the injector. Whatever fuel does not get send to the injector from the rail is sent back to the tank. There is a line from the back of the head that re enters the top of the tank. Clear as mud?

 

Ok cool thanks for the reply! So how do you tell if the CP3 is going bad vs say the injector?

 

If you never added a 2 micron filter more than likely a injector will go well before a CP3.
Injectors have several indicators of failure or failing. Hard start long cranking, White smoke on start up. Fuel knock at idle. and of course melted piston!
CP3 will last a long time things that fail on it are FCA failure and front seal leaking fuel into the oil. Quick test for the CP3 is unplug the FCA that makes full rail pressure engine will knock plug it back in should take less than 20 seconds to recover.