1986 Fuel Pump Resistance
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1986 Fuel Pump Resistance
Have a 1986 L98 which was sitting for a while. Had some hard start/very rough idle scenarios, and finally had a chance to come back to it for diagnosis. I disconnected the 3 pin connector @ the tank by the filler neck and checked resistance of the pump between the black and tan wires. I'm getting around 20 ohms. Does anyone know off hand what a healthy pump's resistance should be? I brought out my power supply and supplied 12v to the connector to run the pump and check pressure at the rail. Pump didn't sound too great, and took 30+seconds to build 35psi.
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Joined: Mar 2013
Posts: 54
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I tested it again today, and once it builds to 35psi I can turn off the pump and itll hold for a while (30+mins). I checked resistance in the cold condition vs after running the pump for a minute and it quadruples to the point where there's barely any current being run through it. You can hear the pump progressively getting slower as it's being powered. I'm thinking I'll need to pull it out and inspect or just replace. Could be the original pump for all I know 
Last edited by 85'irocz; May 17, 2020 at 08:34 PM.
