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bpu699 bpu699 is offline
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Join Date: Apr 2007
Location: wisconsin
Posts: 2,539
Odd. Added msd now fuel pumps buzz?

Really weird. My permatune failed, so I added the msd. Pretty much immediately heard a loud buzzing from the engine compartment. Posted threads about my Cdi buzzing, as it was loud enough to hear in the cabin with the windows up.

Went to harbor freight, and got the stethoscope they sell. Listened to the Cdi, and it was quiet. Listened to the fuel pump, and it was buzzing. Front, is louder also.

Really odd, as I have never noticed the sound before. The front fuel pump is actually new, as of this year.

Car runs fine, isn't lean. Afr is fine. If I pull either relay, car still idles though the running fuel pump gets even louder.

Is there any plausible way that adding an msd could have effected the pumps?

I plan to check the amp draw in the morning. May need to check the fuel filter, though that's less than 500 miles old.

Anything else to check? Fuses?

I know it could be a lot of things, but I swear adding the msd caused it. Before that, I had to touch the fuel pump to make sure it was running. I never heard it buzz from outside the car.

Any help appreciated.
Old 11-01-2014, 06:18 PM
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