Ohms resistance of spark plug wires

Wire resistance varies significantly by manufacturer and application anywhere from a few ohms to 1000 to 3000 ohms/ft.

Engine manufactures have a nominal resistance per length (typical) recommendation and a maximum limit.

The typical maximum is 10,000 ohms.

Suggest you compare wire resistance of all wires. Any wire that is more than double the others would be suspect.

What you can't measure with an ohm meter is breakdown voltage (leakage) of the dielectric. Plug wires don't last forever and on modern vehicals should be replaced at 75k to 100k miles minimum.

Disconnect the ignition coil output wire at the distributor cap.
Connect a spark plug to the end of the ignition coil output wire which you just disconnected.
Connect a ground wire to the threaded portion of the spark plug.
Disconnect the ignition coil ground wire from the negative terminal on the coil (Green Wire).
Connect one end of a ground wire to the ignition coil negative terminal.
Turn the ignition switch to the ON position.
Tap the other end of the ignition coil ground wire jumper on an good grounding point (for example the battery negative terminal) and look for sparks at the spark plug that correspond to the frequency of your tapping of the ground wire.
If you have a good spark at the spark plug, the ignition coil is good.
If you don't get a good spark, check for approximately 12 VDC from the coil positive terminal (black wire) to ground with the ignition switch in the ON position. You should also get approximately 12 VDC from the coil negative terminal (Green wire) to ground
Ignition Coil Resistance Check

In addition to the test above, you may elect to perform an ignition coil resistance check as confirmation of the coil's condition.

Check the ignition coil primary coil resistance by connecting an ohmmeter between the positive (Black wire) and negative (Green wire) terminals on the coil. The resistance should be 0.4 to 0.6 ohms.
Check the ignition coil secondary coil resistance by connecting an ohmmeter between the coil output terminal and the ignition coil negative terminal. The resistance should be 5000 to 7200 ohms.

You may have a bad coil or bad ground or wire connection

Hard Start
Checks
Action
Definition: Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.
Preliminary
• Refer to the Powertrain On Board Diagnostic (OBD) System Check .
• Refer to Important Preliminary Checks .
• Refer to Visual/Physical Checks .
• Search for bulletins.
Sensor/System
• Check Engine Coolant Temperature (ECT) sensor for being shifted in value. Connect a Scan Tool and compare the Engine Coolant Temperature with the Intake Air Temperature on a cold engine. The ECT and IAT should be within ± 3°C (5°F) of each other. Check the resistance of the ECT sensor if the temperature is out of range with the IAT sensor. Refer to Temperature vs Resistance . If the ECT sensor resistance is not within the specification, refer to DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage or DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage .
• Check the throttle body inlet screen for foreign objects or damage that may affect the MAF sensor airflow sample. Refer to Throttle Body Assembly Replacement .
• Use a scan tool in order to check the IAC operation. Refer to Idle Air Control (IAC) System Check .
• EGR system. Check the for the following conditions:
- EGR pipes and adapter for vacuum leaks.
- Remove the EGR valve and check for a stuck open pintle. Refer to Exhaust Gas Recirculation Valve Replacement .
Fuel System
• Check the fuel pump relay circuit for proper operation. Refer to Fuel Pump Electrical Circuit Diagnosis .
• Check for incorrect fuel pressure. Refer to Fuel System Pressure Test .
• Check the fuel injectors. Refer to Fuel Injector Solenoid Coil Test .
• Check for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Test .
Ignition System
• Check for proper ignition voltage output by using the following steps:
- Clip the spark tester J 26792 to engine ground.
- Connect one end of a spark plug wire to the spark tester while leaving the other end of the spark plug wire to the coil being tested.
- Connect one end of another spark plug wire to the other coil tower.
- Connect the other end of the spark plug wire to ground.
- Crank the engine while observing the spark tester. A crisp blue spark should be observed.
- Repeat the above steps for each coil.
• If an adequate spark is not present at the coil(s), check for the following conditions:
- Coil(s) - Cracks, carbon tracking/arcing, or a resistance value outside the specified range.
Coil Resistance
5000 - 8000 ohms (5K - 8K ohms)
- Spark Plug wires
• signs of arcing/cross
• cracks
• carbon tracking
• firing
• plug boot damage
• pinched or improper routing
• high resistance
- Spark plug wire resistances should measure less than the specified value.
VIN 1 Spark Plug Wire Resistance
7000 ohms (7K ohms).
VIN K Spark Plug Wires Resistance
10000 ohms (10K ohms).
Important: Spraying the secondary ignition wires with a light mist of water may help locate an intermittent problem. Ignition components will arc to ground when a secondary component is malfunctioning.
- Defective module.
- Ignition System Wiring - Loose ignition module feed or ground connection, or damaged system wiring.
• Remove spark plugs and check for the following conditions:
- Fouled plugs
- Cracks
- Wear
- Improper gap
- Burned or damaged electrodes
- Improper heat range or reach
• If spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
Engine Mechanical
• Excessive oil in combustion chamber-Leaking valve seals. Refer to Engine Mechanical.
• Low cylinder compression. Refer to Engine Mechanical.
• For incorrect basic engine parts. Inspect the following:
- Cylinder heads
- Camshaft and valve train components
- Pistons, etc.
- Refer to Engine Mechanical.

Use a multi-meter, turn it to ohms, and check the resistance in the coil circuit. All should be similar- showing resistance of only a few ohms, typically. High resistance in the circuit indicates a bad coil.

Or you could just check for spark on each coil to plug wire. Check the spark at each plug wire end terminal with the engine cranking over. If spark is a strong, blue spark, that coil is probably good.

Usually, about 1,000 ohms per inch is acceptable for spark plug wires. You also use an ohm meter to check coils. Primary resistance is typically low-about 1 or 2 ohms. Secondary resistance is typically high-about 7,000 - 12,000 ohms. It is specific for different coils, you would have to see the coil specs for your Toyota. Register for free at autozone.com, giving make, model, year, and engine size. The repair guides there may have the coil specs. It would also show how to test the coils.

test the spark plug wire for ohms resistance, inspect the spark plug, test the coil for ohms resistance. run a compression test to see if it is the cylinder lost compression (valve job - cracked head or blown gasket)
Best regards
Ck

The multimeter can read the resistance and if it is not open or shorted out, I'd say that your readings are in the normal range, comparing each resistance with each other + or - 10%.

I looked up the resistance readings on my online resource, but they did not list it specifically.
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I looked up the following on autozone.com:

There are 3 dual-tower ignition coils that are part of the ignition control module (ICM). The ICM contains coil driver circuits that command the coils to operate. The Powertrain Control Module (PCM) controls each dual-tower ignition coil by transmitting timing pulses on the ignition coil control circuit to the ICM for the proper coil to enable a spark event.

1. Inspect the spark plug wires for proper orientation.
2. With the ignition OFF, remove the fuel pump relay.
3. Crank the engine and test for a strong spark on each cylinder spark plug wire using a suitable spark plug tester. Ground the companion cylinder spark plug wire of each cylinder when it is tested.
   
   If a strong bright blue spark is present on all of the cylinders, remove and inspect all of the spark plugs for proper torque, proper gap, wear, damage, and fouling. Replace the spark plugs if necessary. If there is no spark on any of the cylinders, test the ignition voltage circuit of the Ignition Coil Module (ICM) for an open/high resistance or short to ground, or test the ground circuit of the ICM for an open/high resistance, or a faulty ICM. The wire circuit resistance should measure less than 3 ohms. If there is no spark on any of the cylinders, or spark is weak or intermittent, test the IC circuit for an open/high resistance, or a faulty ICM. The wire circuit resistance should measure less than 3 ohms. If spark is present on one or more of the cylinders, inspect and test the spark plug wires for arching, cuts, rubbing on other components, and proper resistance. If all tests are normal, then the system is operating correctly.
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Spark Plugs Spark plugs ignite the air and fuel mixture in the cylinder as the piston reaches the top of the compression stroke. The controlled explosion that results forces the piston down, turning the crankshaft and the rest of the drive train. The average life of a spark plug 30,000 miles (48,300 km). On the 2.2L (LN2),engine the life of the spark plug is 100,000 miles (166,000 km). Part of the reason for this extraordinarily long life is the exclusive use of unleaded fuel, which reduces the amount of deposits within the combustion chamber and on the spark plug electrodes themselves, compared with the deposits left by the leaded gasoline used in the past. An additional contribution to long life is made by the High Energy Ignition (HEI) system, which fires the spark plugs with over 35,000 volts of electricity. The high voltage serves to keep the electrodes clear, which suffer less pitting and wear compared to breaker point ignitions. Fig. 1: Breakdown of a common spark plug
Fig. 2: Heat range on spark plugs explained
Nevertheless, the life of a spark plug is dependent on a number of factors, including the mechanical condition of the engine, driving conditions, and the driver's habits. When you remove the plugs, check the condition of the electrodes, they are a good indicator of the internal state of the engine. Since the spark plug wires must be checked every 15,000 miles (24,000 km), the spark plugs can be removed and examined at the same time. This will allow you to keep an eye on the mechanical status of the engine. A small deposit of light tan or rust/red material on a spark plug that has been used for any period of time is to be considered normal. Any other color, or abnormal amounts of wear or deposits, indicates that there is something amiss in the engine. Fig. 3: Explanation of the spark plugs numbering system ---
Spark Plug Wires INSPECTION & TESTING Every 15,000 miles (24,000 km), inspect the spark plug wires for burns, cuts, or breaks in the insulation. Check the boots and the nipples on the distributor cap. Replace any damaged wiring. General Motors requests that you replace your spark plug wires every 30,000 miles (50,000 km). The resistance of the wires should be checked with an ohmmeter. Wires with excessive resistance will cause misfiring, and may make the engine difficult to start in damp weather. To check resistance, remove the distributor cap, leaving the wires in place. Connect one lead of an ohmmeter to an electrode within the cap; connect the other lead to the corresponding spark plug terminal (remove it from the spark plug for this test). The following chart gives resistance values as a function of length. Replace any wire which shows a resistance over 30,000 ohms.

• 0–15 in. (0–38cm): 3,000–10,000 ohms
• 15–25 in. (38–64cm): 4,000–15,000 ohms
• 25–35 in. (64–89cm): 6,000–20,000 ohms
• Over 35 in. (89cm): 25,000 ohms

It should be remembered that resistance is a function of length; the longer the wire, the greater the resistance. Thus, if the wires on your car are longer than the factory originals, resistance will be higher, quite possibly outside these limits.

remove electrical plug from coil,with test light check tosee if u are getting power to the coil with the key on.(remove fuel relay during the testing) if there is power to coil then check resistence on coil. with plug still disconnected.take ohm meter and connect to the two outside plugs to check ohm resistance 0.45 - 0.65 ohms then use ohm meter to check secondary resistance.connect ohmmeter across the two secondary terminals of each coil. resistance 11.5-13.5 k-ohms. if all checks out test wires and plugs. hope this will help!!!

check with inline spark tester between the coil and the plug wires for fire. also check the sparkplugs for a fouled out condition. if all checks out then check the coil with ohm meter. unplug the ignition wire connector from the coil. there should be 3 terminals on the coil. connect the ohm meter to the center pin and the other to either outside pin to check primary resistance. then using the ohm meter check the secondary resistance by connecting one end of ohm meter one tower on coil and the other end of ohm meter across to the opposite side of coil to check resistance. primary resistance--0.95- 1.20 ohms secondary resistance-- 11,300 to 13,300 ohms. if it does not check out then replace the coil.