Diagnostic Aids
WARNING: This page is about a different car, the 2000 Isuzu Hombre. However, it is still accessible from the selected car via links, so may be relevant.
Inspect IAC valve connector for proper connection. Inspect throttle stop screw for signs of tampering. Inspect throttle linkage for signs of binding or excessive wear. A slow or unstable idle may be caused by one of the following:
- Fuel system too rich or too lean.
- Foreign material in throttle body bore or in air induction system.
- Leaking or restricted intake manifold.
- Excessive engine overloading.
- Too high a viscosity engine oil.