What is Stroboscopic Timing of an Engine

What is Stroboscopic Timing of an Engine?

Stroboscopic timing is the measure of time required to ignite an engine by a spark coming through the spark plug by a stroboscope light. Using stroboscopic timing, you can fine-tune your engine timing to work at its optimum condition. It is very easy to measure stroboscopic timing; all you have to do is flash the light from the strobe at the timing marks on the engine. However, you need to factor in other adjustments before carrying out the timing test. Read on to find out what is stroboscopic timing and how you can measure and learn how to adjust the timing for a better performance.

What is Ignition timing?

A strobe light having neon or xenon light indicates the stroboscopic timing. However, before you get to know what stroboscopic timing is, you need to familiarize yourself with the ignition timing first.

Ignition timing

The ignition system is responsible for igniting the fuel in the combustion chamber with a spark from the spark plug so that your car can start. As the spark fires the fuel, a controlled explosion takes place inside the chamber, which causes the crankshaft to rotate and allows your car to move. A marked crankshaft pulley passes by fixed points on an engine every time a spark fires.

In case of a fault in the ignition system, the ignition timing starts to vary. Following are the two situations that can occur in case of a misfired spark from the spark plugs:

Advance timing

If the spark from the spark plug fires before the engine’s piston reaches its top, the controlled explosion inside the engine will produce far less power.

Retard timing

Alternatively, if the spark from the spark plugs fires while the piston moves downwards, the engine’s pressure will dissipate, causing a very weak explosion in the fuel, thus not allowing the engine to give out its maximum output.

It is also a good idea to change the spark plugs. But make sure you buy good quality spark plugs so that they don’t need to be replaced now and then.

What is Stroboscopic timing?

To determine if the ignition timing has an issue, you need to use a strobe light to measure the ignition timing. The reading you get would then be referred to as the stroboscopic timing. As the spark fires and the crankshaft pulley’s timing mark passes by the engine’s fixed points, the strobe light flashes. The stroboscopic effect makes the mark look stationary as the pulley rotates.

Before you measure the stroboscopic timing, you need to find out the ignition timing specification for your car. Refer to your car’s owner’s manual to determine the exact specification recommended for your car and engine type.

You need to buy a strobe to measure the stroboscopic timing. It is advisable to buy a xenon strobe even though it is more expensive than the neon one since it shines brighter.

Measuring the Stroboscopic timing

Once you have the strobe, follow the following steps to measure the stroboscopic timing:

Step 1 – You have to locate the crankshaft pulley and look for its timing marks. If the marks are not easily visible, use a white marker to highlight the marks.

Step 2 – Next, you have to locate cylinder number 1 of the engine. Refer to your car’s owner’s manual if you are not sure.

Step 3 – A strobe has three leads. The red lead is connected to the battery’s positive terminal, the black one is attached to the battery’s negative terminal, and the third one is attached to the plug wire of the number 1 cylinder of the engine.

Note: It is advisable that you check the high-tension circuit in the ignition system before attaching the strobe so that the reading is not affected by a fault in the circuit. Also, check the battery’s leads and connections to ensure that the power is effectively supplied to the system.

Step 4 – Start the engine and notice the temperature gauge. The temperature reading should be in the middle of the gauge.

Step 5 – Now, notice the stroboscopic timing. Compare the readings with ones specified in the car’s owner’s manual to determine if the adjustments are necessary.

Adjusting the Ignition Timing

If your car has a vacuum-advanced ignition timing, you need to remove the vacuum line from the distributor and seal the line with a small bolt to prevent the vacuum leak while the timing is being adjusted.

Follow the following steps to adjust the ignition timing if it is not similar to the recommended timing:

Step 1 – You have to lactate the adjusting nut on the distributor and loosen it to allow the rotation of the distributor.

Step 2 – Using a glove on your hand, keep making adjustments from the distributor while noticing the timing marks with the strobe.

If the timing is advanced, rotate the distributor clockwise to retard the timing, and similarly, if the timing is retarded rotate the distributor counterclockwise to advance the ignition timing.

Step 3 – Now, tighten the adjusting nut on the distributor once the timing is set so that it appears to be idle.

Step 4 – Push the accelerator quickly to increase its RPM and release it so the engine falls back to idle and you can remeasure the stroboscopic timing.

Ensure the new timing is in accordance with the recommended timing in the manual; otherwise, you’ll have to do the adjustments again.

Step 5 – You can skip this step if it isn’t applicable. Reattach the vacuum pipe to the distributor if you removed it.

And there you go, easy ignition timing adjustments. If the strobe does not light up properly, your car’s battery might be an issue. Test the battery to see if it has the right amps. If not, you have to either charge it using a car battery charger or replace it with a new battery. You should thoroughly inspect your car’s ignition system and check and replace any fuses to make sure the system works properly.


Understanding what is stroboscopic timing can help you adjust your car’s ignition timing to make your engine work at its maximum capacity. Measuring the timing with a strobe is an easy task that saves you an unnecessary trip to the workshop.