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Spark Test

  1. Remove duct between air cleaner and intake plenum air connector. Disconnect cruise control, accelerator, and throttle cables (automatic transmission only).
  2. Remove 6 hoses from idle speed control pipe. Remove 2 bolts and idle speed control pipe from intake plenum air connector. Remove oxygen sensor wire from clamps. Disconnect hose from PCV pipe. Remove 2 bolts and disconnect PCV pipe from cylinder head covers and throttle body.
  3. Disconnect hose from intake plenum air connector. Remove 2 bolts, loosen clamps, and remove intake plenum air connector. Remove oil filler cap. Remove 5 nuts from TOYOTA TURBO labeled ignition coil pack cover, and lift off cover.
  4. Remove nut and disconnect No. 1 and No. 2 wires and clamp from ignition coil. Move ignition coil pack with bracket out of the way and remove all spark plug wires from spark plugs.
  5. Remove all spark plugs. Install oil filter cap. Install spark plug wires onto the original 6 spark plugs. Ground each spark plug securely.
    CAUTION: Ignition coil primary or ignitor circuit damage can result if each spark plug is not securely grounded.
  6. Disconnect solenoid resistor block and cold start injector connector. Cold start injector is on bottom of air intake chamber. Solenoid resistor block is on top of right side shock tower (4-wire connector).
  7. Crank engine and check for consistent Blue spark across plug gaps. If all spark plugs do not fire, check ignition feed to coil pack and ignitor circuits. See IGNITION FEED CIRCUIT TEST under IGNITION COIL in this article.
  8. Verify camshaft sensor signals are received by ECU. See IGNITOR TEST in this article. Also, verify camshaft sensor moves when engine is cranked.
  9. If only one or 2 spark plugs show an inconsistent spark across the gap, test that particular coil pack for ignition coil primary resistance as well as spark plug wire resistance. See IGNITION COIL RESISTANCE and IGNITION HIGH-TENSION WIRE RESISTANCE tables in this article.
IGNITION HIGH-TENSION WIRE RESISTANCE

Application Ohms
Supra (7M-GTE) 25,000 Max. Per Wire
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