Sounds like a bad fuel injector. Back in the day we would let them runout in the parking lot and when they stalled we would rip off the intake plenum as fast as possible and ohm check the injectors. They should be around 13 ohms. If they are significantly less, say 3 ohms, than those injectors are bad. This system bank fires the injectors. Meaning that all three injectors on the front back fire at the same time and all three of the injectors on the back bank fire at the same time. If one injector hoes bad it will shut down the whole bank which will stall the engine.

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