Rough & Unstable Idle

1. Visually check all air hoses, fuel hoses and connections.
2. Check fuel pressure and mixture/idle speed adjustment.
3. Check cold start injector, auxiliary air device and temperature sensor.
4. Check air flow sensor, injectors and injector resistors.
5. Check accelerator control adjustment and air induction system.
6. Check ECU multipin connector and ensure throttle flap housing is clean.
7. Check valve clearance and compression pressure.
8. Retest vehicle with new ECU.