Wrong car... excellent input.

How bad is the noise really? Does anybody have a sound clip? I'd like to pick up an AMS fuel rail when I get their fuel pump kit so I don't have to spend an extra $100 on a Cosworth one...

 

The noise is not that bad. It sounds exactly like I'm sitting in the VW Rabbit Diesel that I drove in college in the 80's.

 

OK, I changed out the fuel rail to a Boomba and I have the same noise. My friend has the Boomba in his car and it's quiet. So now what?? I don't think it's the fuel line. I have AN hose with -6 fittings that came with the AMS rail. I used the same hose with both rails.

I guess there's only 2 variables; something's up with the AN supply hose or something's wrong with the regulator.

 

Could it be the injectors themselves? Just a thought.

 

Some ideas:

If you don't hear it under the hood, maybe it's NOT under the hood? Your fuel line runs under your car, and then right up in front of the driver side firewall.. Pull your back seat off and see if the sound is suddenly very loud. If it is, a line may have been pinched, the pump could be bad, etc. etc.

Why don't you pop open the hood, put your hand on the rubber part of the fuel line in the engine bay and see if you can feel something that may coincide with the sound you are hearing? If you don't feel it on your fuel line, you're not getting pulses of fuel, so it's going to be within the rail, injectors, or engine itself.

Make sure the FPR has the small vacuum tap line reconnected to the top, the bolts for the vacuum line that's attached to the rail are bolted (2 bolts) in the front, and the bolt on the driver side of the engine.. just follow the hose. Make sure all the electrical connectors are seated.

Good luck...

 

The sound changed when installing the AMS Rail and AN Fuel Supply Line. SInce then I've changed from OEM to DW1000 injectors and upgraded to a Walbro in-tank system with ne lines. With each mod, there's been no change in the diesel sound.

I'm going to try to swap to the OEM fuel line using the Boomba rail since it came with a way to connect to the OEM quick disconnect. Maybe the standard rubber fuel line dampens the vibration more than the AN line????

 

Just to add, my Cosworth fuel rail with DW1000's does this as well. Starting to get used to it, however; it was quite annoying the first day of driving.

 

What kind of supply line are you using going from the hard-line to the rail in the engine compartment?

 

Sounds like the regulator or -AN lines are causing the noises. Definitely report back what it ends up being as I'm heading down the "need more fuel" route shortly.

 

Stock, with the hard line adapter that came with the Cossy rail.

Upon low-speed decel when the ECU shuts the injectors off, the noise goes away. Strangely, it's heard on the driver's side near the firewall...

It's got to be the pulses of the injectors vibrating the hard fuel lines somehow. Doesn't make any sense to me, but I'll listen for it when I have my car up in the air after my turbo install.

 

If you still have it with the OEM fuel line, no reason for me to try that.

My buddy with the Boomba rail runs an aftermarket FPR and aftermarket rubber fuel supply hose with a filter and barbed fittings....DW1000s....No noise with his setup.

 

I been led to the conclusion it might be the OEM FPR that causes this issue. I am thinking that I will upgrade the FPR to a Aeromotive, Fuel Lab, or other high quality 1:1 unit.

This will hopefully eliminate the issue and give much more predicable and stable fuel response.

 

I hate to bump an old thread, but was this ever solved?

 

I never got around to trying a different rubber line to dampen the sound. I guess I just got use to driving what sounds like a diesel.

 

Very interesting.... Thanks for the feedback.

Listening to the noise more, it almost sounds like the fuel feed or return line is vibrating underneath the car. Maybe this has something more to do with fuel return line over-pressurization/over-run. I had my fuel pump unit out of the car the other day but failed to drill out my return line orifice because of the ambiguity around that exact procedure on the Evo X.