2nd fuel pressure regulator?

[craftz]

At the back of the engine I was hooking up a turbo coolant line and noticed a vacuum line just hanging. It was cracked and had fallen off. It started at the plenum and was supposed to be hooked up to what looks like a fpr on the rear of the fuel rail. Are there two. I just changed the one on the front and am wondering what this is?

[amnash]

i know what your talking about but i have no idea. i would like to know too

[craftz]

I just had a quick look on Fast and I could not identify it either. Come on, somebody has got to know what this is.

[beacher1B0]

I believe its the Fuel Pressure Damper. Dampins the pulses in fuel flow coming from the Fuel pump.

Yep, just checked Fast. Damper Assy - Fuel. Section 164

[Skym]

That's what I thought as well. But FPR on back of engine is a damper that cancels out the pulses that reverse direction inside fuelrail due to FPR on return part of fuel rail (front of engine) creating a pulse that reverses direction.

When running 2x pumps into a fuelrail (one on each end of fuelrail), the fuel coming together in the middle of fuel rail (where it exits) acts like a damper.

At least that's how I understand how it works from what someone told me.

[beacher1B0]

Ahh, interesting. Never thought about that. I also noticed in Fast that the damper only came on RB20det after 91/08. If i interpreted it correctly.

[craftz]

Thanks for the info everyone. I will check fast again just out of curiosity since I could not find it first time around.