put the key in the run position gage works with tester light at the sending unit i get a pulseing lite turn key to starter mode with key gauge stops workin & no more pulseing lite at the sending unit ground is good to the frame of the car is the problem in the dash

power is cut to the gauge in start(ign 2)so you're Ok there

so let me understand this power is not constant power go,s away & the gauge stops workin???

to check the sending unit, you need to be able to move the float up and down. If the readings are between 73 and 10 ohms, you're good. The gauge is just reading the resistance at the sending unit.

you need to get a multimeter out and check continuity between the pin on the back of the gauge cluster and the connector on the sending unit.

When cranking power is cut to all non essential devices that are not neccessary to help start the car such as gauges/accessories(radio/fan/heater etc)so that as much power as possible is diverted to the starter and ignition to start the car. Like on star trek when Kirk would divert power from other systems(the invisibility shield for instance)so that the phasers would have max power. The exception is power is still available for the headlights/taillights/turn signals/flashers for safety reasons as they are not neccessary to start the car but a person can choose to shut them off at night if the car dies as long as you ain't in danger of being hit.

Gauges work with the key on or in accessory, not in the start position.

so in the run position i get the pulseing lite at the sender hit the starter no more pulseing let off starter still no pulseing lite turn ing to off turn back to run position pulseing .so from the starter position back to run should,nt it go back to puleing

It should go back to pulsing when you let go of the key from start. What happens if you turn the key a little more back but not off? I'm wondering if the ignition isn't sticking a bit from start to run. Does the engine stay running after you let go of the key?

yes eng stays runnin no prob there start position kills the power & do,nt come back

This sounds weird but try moving the ignition switch wires at the base of the colume and at the bulkhead under the hood while in the run postion after the gauge quits. See if maybe you have a bad connection somewhere.Does the temp gauge quit also or just the gas gauge?

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