Cylinder Drop Test
The cylinder drop test is performed when an engine misfire is evident. This test helps determine which cylinder is not contributing the proper power. The easiest way to perform this test is to remove the plug wires one at a time from the cylinders with the engine running.
- Place the transaxle in P or N , engage the emergency brake, and start the engine and let it idle.
Using a spark plug wire removing tool, preferably, the plier type, carefully remove the boot from one of the cylinders.
WARNINGMake sure your body is free from touching any part of the car which is metal. The secondary voltage in the ignition system is high and although it cannot kill you, it will shock you and it does hurt.
- The engine will sputter, run worse, and possibly nearly stall. If this happens reinstall the plug wire and move to the next cylinder. If the engine runs no differently, or the difference is minimal, shut the engine off and inspect the spark plug wire, spark plug, and if necessary, perform component diagnostics as covered in this section. Perform the test on all cylinders to verify which cylinders are suspect.
Ignition Spark Test
Disconnect fuel injector connector(s).
WARNINGWithout disconnection of injector connector, combustible gas may come out from spark plug holes during this test and may get ignited in engine room.
- Remove spark plugs and connect them to high-tension cords (spark plug wires), and then ground spark plugs.
- Crank engine and check if each spark plug sparks.
- If no spark is emitted, inspect high-tension cords, spark plugs, ignition coil, distributor, etc.