Tapping noise associated with fuel system

[kwando]

Hi Dave,

There is one thing bothering me with my car. It is currently turbo charged with a custom kit, running RC 550 injectors, T04E turbo, EMS, and walbo fuel pump.

Just lately i've noticed a tapping noise. When the car is at idle, stereo turned off, and windows rolled up i can hear the slight tapping noise.

Tobi at TC's performance helped me track it down to something linked with the fuel system.

If i kill the car by letting out the clutch in gear, the tapping noise continues until the fuel pump relay clicks over.

The noise was present on stock fuel pump as well, and i just recently changed over to the walbo.

Can the fuel pulsation dampener be the culprit? Or injectors? I know that some injectors make a tick/taping noise.

Everyone i've talked to say to not even worry about it. I cannot hear the noise in a bone stock s2k.

Any ideas???

[repiv]

Offhand, I would say you've got a noisy injector. There is a way to find out what it really is. Use a mechanic's stethoscope and probe each injector when it's making the sound. Also, listen to the pulsation damper, the timing chain tensioner and probe the approximate area of each valve. You can also check the fuel pump itself with the stethoscope. Yank the cover to get at the spare tire and put the probe on the top of the fuel pump. If it's ticking, you'll know it right away. It usually whines or hums. I doubt it's the fuel pump since nothing changed when you went to the Walbro.

[kwando]

dave - i found the source for the ticking. the three fan/condensor fan relays in the fuse box.

i did a search on the other forum and you posted in it.

http://www.s2ki.com/forums/index.php?act=ST&f=22&t=425258

i am running EMS, and my tuned has set the fans to turn on lower than the factory setting. is it possible that the EMS is sending a pulse to the relays causing them to click?

while the relays are ticking the pass side fan blades are pulsating. i can feel the tick on the back of the electric motor.

any help is appreciated.

[repiv]

Looks like fperry has you covered. He's pretty good with stuff like that. It seems likely that it's your EMS that's involved with this issue.