How to Troubleshoot the Ignition System in a Toyota Tacomaby ContributorUpdated November 07, 2017
Items you will need
How to Troubleshoot the Ignition System in a Toyota Tacoma. There are multiple ways to troubleshoot a Tacoma's ignition system for problems. The test you should perform first involves testing the spark plugs and wires. If they don't produce sparks, you must test several other parts.
Remove the Tacoma's ignition coils with the igniter from the spark plugs, then remove the plugs. You must disconnect the spark plug wires from the plugs on a 3RZ-FE engine.
Install the spark plugs to the ignition coil or spark plug cables, attach the ignition coil electrical connector and disconnect the electrical connection from each fuel injector. Ground the spark plug to a metal spot on the engine.
Crank the engine and look for a strong blue spark on the plug. Check the connection to the ignition coil and igniter if no spark appears.
If No Spark Appears
Inspect the spark plug wires' resistance if the truck has them. The resistance should measure 25,000 ohms on an ohmmeter. Replace any wires that don't meet specifications.
Check the ignition coil's power supply. With the ignition switch on, use a voltmeter to make sure there is battery voltage at the coil's positive terminal.
Measure the resistance of the ignition coils. Unplug all connectors and test the primary resistance between the positive and negative terminals. It should be 0.67 to 1.05 ohms.
Test the secondary resistance between the positive terminal and high-tension terminals. The resistance 9.3 to 16.0 kilo-ohms on a 5VZ-FE Tacoma engine and 9.7 to 16.7 kilo-ohms on the others.
Use the ohmmeter to check the camshaft position sensor's resistance. Measure between the G+ and G- terminals on the sensor connector. The resistance should be 185 to 275 ohms on a 2RZ-FE engine and 835 to 1,400 ohms on the rest.
Move to the crankshaft position sensor, measuring the resistance between its connector terminals. It should measure 1,630 to 2,740 ohms.
Look over the wiring between the engine control module and the igniter. If the wiring is okay, the problem is likely the igniter.
All resistance specifications listed are for a cold engine. Warmer temperatures will affect the specifications.
Avoid cranking the engine more than one or two seconds at one time to prevent injecting gasoline into the engine. Cranking the engine more than 5 to 10 seconds can overload the engine with gasoline. Use as much insulation as you can when holding the wires. Avoid standing on a wet surface while testing and don't lean on the car's body.