What is the Electronic Spark Control all about?

The ignition of the air/fuel mixture in the engine’s combustion chambers is minutely controlled by the engine timing. On the engine, there are one or more knock sensors – little piezoelectric sensors – that measure vibrations that the engine produces. If there are excessive vibrations, the powertrain control module uses the information from the knock sensors to determine how adjustments should be made.

These vibrations can usually be controlled by slight engine timing adjustments. The powertrain control module communicates the adjustments that are required for the electronic spark control module to operate properly. These adjustments advance or retard the timing ever-so-slightly to compensate for the engine vibration. The process occurs in the background while the engine is running, and you would never be able to detect the adjustments unless there is a problem with the system. If the ESC module is faulty, spark knock may occur from the engine with over-advanced timing. The engine light will illuminate, often with knock sensor codes or an ESC module code.

Keep in mind:

• The electronic spark control module is separate from the knock sensor but works closely with it. Similar symptoms can be produced by both parts, so proper diagnosis is essential.
• An ESC code in the powertrain control module refers to electronic spark control, not electronic stability control.

How it's done:

• The electronic spark control is verified it needs replaced
• The defective electronic spark control module is removed
• The new electronic spark control module is installed and engine scanned for codes
• The engine is started and the electronic spark control is tested for operation
• The vehicle is road tested for proper operation of electronic spark control

Our recommendation:

There is no maintenance required for the electronic spark control module, though its operation can be checked any time a Check Engine light is being diagnosed. If the engine’s electronic spark control module is faulty, it will require one of our expert technicians to replace it.

What common symptoms indicate you may need to replace the Electronic Spark Control?

• Check Engine light is on
• Engine stumbles or stalls when accelerating from a stop
• Knocking noise from the engine on acceleration from a stop

How important is this service?

The electronic spark control system isn’t a safety issue; however, if left unattended, it can cause internal damage to your engine from prolonged advanced spark. A neglected repair can cost thousands of dollars down the road, and as such should be addressed as soon as feasible.