The ASD relay provides the power to coil and pump, it needs to see a few things, 1, needs crank sensor signal, 2, needs dist signal, both of these sensors are commen to failure, scan tool can be helpful here to monitor data, also voltmeter is helpful to, just back probe the sense return signals at the PCM connectors. Also these trucks had a harness problem on left side fender area near the PDC relay box that feeds the ASD relay pin 87, ( this should light with a test light, key on,) open circuit in the harnes, has to be cut open to check. you can also jump this relay, pin 87 to 30, 87 being J2 ign feed, 30 going to coil and pump being a 1990 truck remote stater should not be a issue, unless it was just put in, then just unplugg it. GOOD LUCK. RDJRP
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