Idle Speed

CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. DO NOT allow tachometer terminal to become grounded or ignitor and/or coil may be damaged.

NOTE: Idle speed is controlled by the computer and idle speed control system.

Install tachometer to proper terminals. See Figure. Start engine and note if idle speed is within specification. See IDLE SPEED SPECIFICATIONS TABLE in this article.
If idle speed is not within specification, check the ISC valve, wiring and ECU. See IDLE SPEED CONTROL (ISC) SYSTEM in SYSTEM/COMP TESTS article.

IDLE SPEED SPECIFICATIONS

Application

Idle RPM

LS400

⁽¹⁾ 600-700

⁽¹⁾	Midpoint of range is preferred.