C15 Acert Fuel Pressure Guage

Mine isn't actually disconnected, the wires are just hard to see. Disconnecting or adding a resistor to fuel wire changes the fuel mapping.

 

All the resistor thing does is trick the ecm Into thinking your fuel is above a certain temp. Then it adjust the fuel map to compensate for the warmer fuel. It only benefits for a short time..... ie after you just fueled up or when you start in the morning. After you have been driving for a while it negates because your fuel has been heated up running through the head. Your pressure is within specs for cat. But if your like me I like my own specs. I don't like shimming the spring. Dont stretch the spring it will eventually collapse back to original tention over time. Get the new style pump with the updated spring. Use a check valve from an Acert cat. It is set a little stiffer. You can take apart the check valve and shim the spring in it, but you have to be very, very careful doing it. DO NOT GO OVER 120 lbs you will posibaly blow o-rings on the injectors.

 

This the gauge I use to check my pressure. It isn't a dash mount. It goes up to 160 lbs. It is gliserin filled to keep it from vibrating with the fuel pulses. I like to connect it at the plug in front of the fuel port adapter my opinion is you get a more accurate reading.

 

Yeah it's mechanical. I bought a spare from Cat before Christmas because the one in the dash doesn't look so good because some clown (me) damaged the glass.
They are an earthmover gauge so you should be able to get one from any Cat dealer. Just quote the part # on my gauge. If you've got a mechanical oil pressure gauge it shouldn't be any more of a problem than that. Mine uses Aeroquip hose and if it's good enough for a B52 bomber it's good enough for a truck lol