Electrical problems
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Electrical problems
i have a 1980 ford f-150 with a 302 motor and i am having a problem with the instrument gauges. When i have the key on the gauge for the oil pressure the neddle goes all the way to the H side and stays there until i start the truck then the neddle goes to the L side and stays there. and it won't move at all. But the other problem i am having the gauges is the fuel n temp. gauges r not working at all. The fuel gauge stays on the E mark and the temp. gauge stays on the C side of the gauge no matter if the key is on or off. Does anyone have any ideas on what the problem could b n how to fix it?
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Joined: Sep 2003
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From: Right Next to U
Quote"When i have the key on the gauge for the oil pressure the neddle goes all the way to the H side and stays there until i start the truck then the neddle goes to the L side and stays there."
Oil pressure sending switch is defective.
Quote"the fuel gauge stays on the E mark."
Bad connection from the fuel tank or tank sending unit defective.
Quote"and the temp. gauge stays on the C side of the gauge."
Temp sending unit defective or loose/disconnected wire.
Oil on (temp/Oil)switch connection will cause a bad/loose connection also. Sending units for all 3 are not really expensive but it is important to have a way to know what your engine is doing while driving, any of the three senders not giving you feedback on the condition of your engine could leave you F.O.R.D. (Found On Road Dead) or stranded.
Oil pressure sending switch is defective.
Quote"the fuel gauge stays on the E mark."
Bad connection from the fuel tank or tank sending unit defective.
Quote"and the temp. gauge stays on the C side of the gauge."
Temp sending unit defective or loose/disconnected wire.
Oil on (temp/Oil)switch connection will cause a bad/loose connection also. Sending units for all 3 are not really expensive but it is important to have a way to know what your engine is doing while driving, any of the three senders not giving you feedback on the condition of your engine could leave you F.O.R.D. (Found On Road Dead) or stranded.
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Joined: Jan 2001
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From: Virginia
Find the wire down by the oil filter that goes to the oil pressure sending unit. Turn the key to run, and while someone is watching the gauge inside, put the sending unit wire on a good ground on the engine block. The gauge should swing full scale one direction. Then take the wire off ground and let it hang in the air. The guage should swing full scale the opposite direction. If this works, then the guage and wiring are ok, and the sending unit is bad.
Find the wire to the temp sending unit, and do the same test for the temp gauge to see if it works.
Go back to the gas tank, and find the sending unit wire on top of the tank. Take it off and do the same test as the other guages. If it works, then the sending unit in the tank is bad.
Find the wire to the temp sending unit, and do the same test for the temp gauge to see if it works.
Go back to the gas tank, and find the sending unit wire on top of the tank. Take it off and do the same test as the other guages. If it works, then the sending unit in the tank is bad.
