Tacoma 2.4L 4-Cyl. & 2.7L 4-Cyl., T100 2.7L 4-Cyl. & 4Runner 2.7L4-Cyl.

Distributorless Ignition System (DIS) uses the Engine Control Module (ECM) for determining ignition timing (spark advance). The ECM may determine ignition timing (spark advance) based on various input signals, engine RPM and knock sensor input signal.

NOTE: Camshaft position sensor may also be referred to as cam position sensor.

Conventional distributor and pick-up coil have been replaced by a camshaft position sensor and crankshaft position sensor. Camshaft position sensor and crankshaft position sensor deliver input signals to ECM. The ECM detects the standard crankshaft position based on camshaft position sensor input signals, and the actual crankshaft position and engine speed by the crankshaft position sensor input signals. Camshaft position sensor is located at driver's side front corner of cylinder head, just in front of the intake manifold. See Figure-21. Crankshaft position sensor is located near crankshaft pulley, just above oil pan on driver's side of engine. See Figure-21. For knock sensor location, see REMOVE/INSTALL/OVERHAUL article.

The ECM uses 2 ignition primary control signals to the ignitor for the ignition coils. The DIS uses 2 ignition coils with internal ignitors to fire 2 cylinders simultaneously using the same ignition coil. See Figure. Cylinders No. 1 and 4 fire together and cylinders No. 2 and 3 fire together. Cylinder No. 1 is front cylinder at timing chain end of engine and cylinder No. 4 is the rear cylinder at flywheel end of engine. Ignition coils are mounted near front of cylinder head. The ECM monitors IGF circuit at the ignitor to ensure ignition coils have fired.