California vehicles only Check Connector V+ E1, TE1 ECU VF TE1 OX1 OX2 H1 +B (+B1) E1 Oxygen Sensor Sub-Oxygen Sensor Sub-Oxygen Sensor Heater FI3383 1. There is no voltage between ECU terminals VF1 and E1. ECU Voltmeter V E1 VF1 2. There is specified voltage between ECU terminal VF1 and body ground. NO OK Check wiring between ECU terminal E1 and body ground. OK BAD Try another ECU. Repair or replace. FI2947 SST Check Connector E1 TE1 V+ VF1 Voltmeter V SST FI4210 FI4209 Check for suction of air into exhaust system. BAD Repair air suction. OK Check for air leak from air intake system. BAD Repair air leak. OK Check spark plugs. BAD Repair or replace. OK Check distributor and ignition system. BAD Repair or replace. OK Check fuel pressure. BAD Repair or replace. OK Check injectors. BAD Repair or replace. OK Check cold start injector. * BAD Repair or replace. OK Check air flow meter. BAD Repair or replace. OK Check operation of oxygen sensors. OK System normal. BAD Check wiring between oxygen sensors and ECU connectors. BAD Repair wiring. OK Replace oxygen sensors. * Rich malfunction only