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Q: Car will crank but no start... Fuel pump not coming on. New pump, relay, etc. Will start when hot wire runs from pump wires to bat

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We have replaced the fuel pump and relays. Car will crank with hot wire from fuel pump wire harness to battery. ( Wires not getting connection) Tested with test light. When running, car will sometimes stall at red lights or stop signs. Replaced fusebox and car ran for two weeks no problems. but all of a sudden car wouldnt start again, only by hot wire.

My car has 174546 miles.
My car has an automatic transmission.

There are a couple of approaches to take here - either start from the battery and work "towards" the fuel pump, fuse box, ignition switch, fuel pump relay, and wiring connections in between. Or, as you have done, start at the pump with 12v, and move backwards towards the battery. This will require a GM service manual, or wiring diagram at least, with connection locations as well.

I would recommend having a certified technician from YourMechanic diagnose this starting issue, get an accurate assessment of damage and cost estimate for repairs. YourMechanic.com can dispatch a mobile, professional mechanic to your location for this repair.

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