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Engine - Pinging (Spark Knock)

NO:
EG92-002

DATE:
OCTOBER 09, 1992

MODELS
ALL

Title:
ENGINE PING REFERENCES IN OWNER'S MANUAL

Under certain driving conditions, minor engine ping, also referred to as "spark knock", is common for high compression engines such as those used in all LEXUS models. Do not hesitate to inform customers of the following information included in their LEXUS Owners Manual:

"If you engine knock . . .

If you detect heavy knocking, even when using the recommended fuel, or if you hear steady knocking while holding a steady speed on level roads, consult your LEXUS dealer.

However, now and then, you may notice light knocking for a short time while accelerating or driving up hills. This is no cause for concern."





This statement is included in all LEXUS Owner's Manuals on the following pages:

Because all LEXUS models have knock sensors, the following question may arise:

Q: When I hear knocking, does it mean that the knock sensors are not working correctly?

A: Engine control systems with knock sensors operate by modifying ignition timing when knocking is detected. In other words, knocking must be present before the control system acts to modify the timing. This is usually noticeable by a short duration of a light knocking noise and is not cause for concern.