could a bad crank sensor cause the fuel pump not to turn on.If there is a leak in the rollover vaulve on the fuel pump,would that shut off the pump.
Dec 1, 2010 at 5:24 AM
fuel
1997 DODGE TRUCK
BILLZY70
- MEMBER
- 8 POSTS
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CARADIODOC
- ✓ASE Certified Mechanic
- 34,321 POSTS
Absolutely. You won't have spark either, so it's important to check both systems. Don't just jump on the first thing that you find not working.
The fuel pump or pump relay, ignition coil(s), injectors, alternator field, and oxygen sensor heaters all get their power from the automatic shutdown (ASD) relay. The Engine Computer turns that relay on whenever there is engine rotation, (cranking or running), and it knows that by the pulses it receives from the camshaft position sensor and the crankshaft position sensor.
The ASD relay also turns on for one second after turning on the ignition switch. You should hear the hum of the fuel pump for that one second.
caradiodoc
The fuel pump or pump relay, ignition coil(s), injectors, alternator field, and oxygen sensor heaters all get their power from the automatic shutdown (ASD) relay. The Engine Computer turns that relay on whenever there is engine rotation, (cranking or running), and it knows that by the pulses it receives from the camshaft position sensor and the crankshaft position sensor.
The ASD relay also turns on for one second after turning on the ignition switch. You should hear the hum of the fuel pump for that one second.
caradiodoc
Dec 1, 2010 at 5:39 AM
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