1977-79 Models
- Unplug airflow sensor and positive wire from alternator. Install pressure gauge and set valve to OPEN. See TEST EQUIPMENT HOOK-UP in this article. Turn ignition on, without starting engine.
- Unplug control pressure regulator and measure voltage at plug. If none, check power relay and fuel pump relay (if equipped). If voltage is available at pump relay, problem lies with wire connecting control pressure regulator and pump relay.
- If voltage is reaching regulator plug, check resistance across regulator terminals for 20 ohms. If resistance varies greatly, replace control pressure regulator.