Eli_Swer

I just built and installed a braineak ms3x. Shoutout brain for the diy instructions. Ecu seems to be working fantastic, about to do some idle tuning. I noticed when keying on I get a quick 2-3 second buzz from under the driver side dash. Don't think the car did this before the ecu, thinking it's fuel pump relay priming? Saw a couple threads say a constant is an IAC with incorrect frequency or the IAC is running before the car is. The setting for IAC on key on is off and this is NOT a constant buzz but only a few seconds. Any ideas? Should I be worried or just ignore it. Trying to be extra cautious is all.

Eli_Swer

'94 btw.

sixshooter

iTrader: (12)

My fuel pump relay beside the steering column did this when the main 80 amp relay failed open. Could be something else, too.

Eli_Swer

if the relay failed it would have only buzzed once then never again right? I can attach a video shortly.

sixshooter

iTrader: (12)

When the main relay failed a relay under the dash buzzed when the ecu tried to engage the fuel pump. It also buzzed if F/P was jumped to GND in the diagnostic box, iirc.

Eli_Swer

I see, you'll have to forgive me if I'm not following. If this is a f/p relay failure why does my car still run? Failing open would mean the relay is never sending power to the f/p? Or would that mean the relay is ALWAYS sending power to the f/p. If so what are the implications of this?

I do have plans to go to a DW hardwire kit for turbo applications, maybe I'll just do it sooner rather than later.

Eli_Swer

Also is the video of the noise, gotta turn your volume up to hear it. I'm beginning to think it's just the fuel pump priming and I was second guessing my work after building the entire ms3x and installing it, not thinking myself capable.

Nevermind the cel, I think it's setup to show CANbus functionality rn? I'll have to look into it.

sixshooter

iTrader: (12)

Are you sure it isn't the door buzzer key reminder?

Eli_Swer

Positive, removed that ages ago. Almost positive it's fuel pump. Can hear the fuel rush to fill the lines simultaneously with the buzz. Pardon my overreaction.