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Q: Why does my Tahoe start with the fuel pump relay pulled out or left in?

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I been having starting problems at times.. My 1998 Chevrolet Tahoe with the 5.7 Vortec will crank right up then die.. Then you try to crank it again and it fires up and it's fine it seems the rest of the day.. I'm just puzzled I can't understand why it starts with the Fuel Pump Relay pulled out and with it in? I was told to pull the relay and see if it stopped it from starting. I was told it should not start with Fuel Pump Relay out ,, but funny thing it does start an run.. My question is..Is my Fuel Pump Relay bad??

My car has 220000 miles.
My car has an automatic transmission.

Hi there. Check to see what relay you have pulled. If indeed you removed the fuel pump relay and the engine still starts up, then check the oil pressure switch. An oil pressure switch will kept the engine running as it passes battery voltage to the fuel pump. When the engine builds up oil pressure, the oil pressure switch sends voltage to the fuel pump and bypasses the fuel pump relay. Unplug the oil pressure switch and see if the engine stops running. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, who can assist you with why your vehicle is still running with the fuel system relay removed.

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