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3) Connect an engine tachometer. Crank engine. Ensure ignition coil primary current toggles on and off. Using scan tool, read engine cranking speed (item 22). Compare tachometer and scan tool RPM display. Go to next step. 4) If engine fails to start and tachometer reads zero RPM when engine is cranked, check for broken timing belt or faulty CKP sensor. If CKP sensor is suspected, substitute known-good CKP sensor. Repeat test procedure. If engine fails to start, tachometer reads zero RPM, and ignition coil primary current fails to toggle on and off, check for faulty ignition coil, ignition circuit or power transistor. If engine starts and readouts agree, go to next step. 5) Ensure A/C switch is in ON position to activate closed throttle position switch. Allow engine to idle. Using scan tool, check engine coolant temperature and read idle speed. See IDLE RPM SPECIFICATIONS table. If RPM is not to specification, check for faulty ECT sensor, basic idle speed adjustment, or idle air control motor. If RPM is within specifications, go to next step. IDLE RPM SPECIFICATIONS TABLE Engine Coolant Temperature Engine RPM -4 F (-20 C) Montero ...................................... 1300-1500 3000GT Non-Turbo .................................. 1275-1475 Turbo ...................................... 1300-1500 32 F (0 C) Montero ...................................... 1300-1500 3000GT Non-Turbo .................................. 1225-1425 Turbo ...................................... 1300-1500 68 F (20 C) Montero ...................................... 1300-1500 3000GT Non-Turbo .................................. 1100-1300 Turbo ...................................... 1300-1500 104 F (40 C) Montero ...................................... 1040-1240 3000GT Non-Turbo ................................... 950-1150 Turbo ...................................... 1050-1250 176 F (80 C) Montero & 3000GT ............................... 600-800 6) On 3000GT, go to next step. On Montero, disconnect CKP sensor connector and MFI relay connector. Using DVOM, check for continuity between CKP sensor connector terminal No. 3 and MFI relay connector terminal No. 1. If continuity does not exist, repair wiring harness as necessary. If continuity exists, go to next step. 7) With CKP sensor connector disconnected, check for continuity between chassis ground and CKP sensor connector terminal No. 1 on Montero or No. 2 on 3000GT. If continuity does not exist, repair wiring harness as necessary. If continuity exists on 3000GT, go to next step. On Montero, go to step 9). 8) Check for voltage between chassis ground and CKP sensor connector terminal No. 3. If battery voltage does not exist, repair wiring harness as necessary. If battery voltage exists, go to step 10). 9) Turn ignition switch to OFF position. With CKP sensor connector disconnected, disconnect PCM connector. Check for continuity |