# ENGINE AND ENGINE OVERHAUL

## ENGINE ELECTRICAL

### Ignition Coil

#### TESTING

##### 200SX (1982–83 Z series engine)

1. Make a check of the power supply circuit. Turn the ignition OFF. Disconnect the connector from the top of the IC unit. Turn the ignition ON. Measure the voltage at each terminal of the connector in turn by touch the probe of the positive lead of the voltmeter to one of the terminals, and touching the probe of the negative lead of the voltmeter to a ground, such as the engine. In each case, battery voltage (12 volts) should be indicated. If not, check all wiring, the ignition switch, and all connectors for breaks, corrosion, discontinuity, etc., and repair as necessary.

   Fig. 1: Ignition wiring diagram 1982–83 200SX

   Fig. 2: Testing battery voltage with voltmeter

   Fig. 3: Checking the ignition coil secondary circuit

   Fig. 4: Testing the power supply circuit — 1983 200SX

   Fig. 5: Checking the ignition coil primary circuit

2. Check the primary windings of the ignition coil. Turn the ignition OFF. Disconnect the harness connector from the negative coil terminal. Use an ohmmeter to measure the resistance between the positive and negative coil terminals. If resistance is 1.04–1.27Ω the coil is OK. Replace coil(s) if far from this specification range.
3. Turn the ignition switch to the OFF position.
4. Disable the electronic fuel injection so engine will not start (disconnect the EFI injection fusible link).
5. Disconnect the high tension cable from the distributor. Hold the cable with insulated pliers to avoid getting shocked. Position the wire about a 1⁄4 in. (6mm) from the engine block and have an assistant turn over the engine using the starter. A good spark should jump from the cable to the engine block or ground.

   NOTE: The 1984–88 200SX, 1989–92 240SX and Stanza vehicles use a highly complex computerized ignition system. For complete testing, flow charts and engine code diagnostic procedures — See Sections 2 and 4.

##### Stanza

###### PRIMARY RESISTANCE CHECK

Testing with a ohmmeter, the reading should be 0.84–1.02Ω for the Stanza models from 1982–86. On 1987 and later Stanza models, a "Mold type" coil is used; first remove the coil wire then connect the leads of an ohmmeter to the positive (+) and negative (-) terminals.

NOTE: Terminals at the bottom of the coil assembly the reading should 0.8–1.0Ω for this type coil. If the reading is more than specified, replace the ignition coil assembly.

###### SECONDARY RESISTANCE CHECK

Turn the ignition key OFF, then remove the high tension and a primary coil wire from the coil using an ohmmeter, set it on the X1000 scale. Touch one lead to a primary terminal and the other lead to the center terminal. The resistance should be 8,200–12,400Ω if not, replace the ignition coil.

NOTE: On some later model vehicles, a power transistor is used with the ignition coil. The ignition signal from the ECU is amplified by the power transistor, which turns the ignition coil primary circuit on and off, inducing the proper high voltage in the secondary circuit. On these models the ignition coil is a small molded type.