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SkidmoreGarage · 07-21-2020, 03:12 PM

What do you mean by "arc-ed the battery"? If it just sparked when getting connected, I'd be surprised it fried an ECM (assuming a good wiring harness). If it was hooked up backwards... Or if the header install crushed some wires that shorted out... Then it would make more sense. Without knowing your exact wiring, have you confirmed that you are getting the constant power as well as the signal to the relay? If the relay appears to be getting a signal and it's a known good unit, try applying 12v directly to the relay power feed and see if it passes through to the pump with key on.

If you don't have a cheap multi-meter, I'd recommend picking one up. Checking for continuity would help you a lot.

07-21-2020, 03:12 PM	#10
SkidmoreGarage Registered User Join Date: Mar 2020 Location: Portland, OR Posts: 335	Re: Fuel pump with LS engine What do you mean by "arc-ed the battery"? If it just sparked when getting connected, I'd be surprised it fried an ECM (assuming a good wiring harness). If it was hooked up backwards... Or if the header install crushed some wires that shorted out... Then it would make more sense. Without knowing your exact wiring, have you confirmed that you are getting the constant power as well as the signal to the relay? If the relay appears to be getting a signal and it's a known good unit, try applying 12v directly to the relay power feed and see if it passes through to the pump with key on. If you don't have a cheap multi-meter, I'd recommend picking one up. Checking for continuity would help you a lot.