Circuit Description
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.
Misfire is detected using Camshaft Position (CMP) and Crankshaft Position (CKP) sensors. When Vehicle Control Module (VCM) senses CKP deceleration not associated with normal engine speed reduction, CMP is used to determine misfiring cylinder. VCM determines misfires on each cylinder and evaluates a random misfire and sets DTC.
Conditions required to set DTC are:
- No CKP, MAF, TP or VSS sensor DTCs set.
- Rough road not detected.
- Engine speed 450-5000 RPM.
- ECT is 19°F (-7°C) or greater.
- System voltage 11-16 volts.
- Fuel level is 10 percent or greater.
- Positive throttle position change is less than 1.9 percent for 100 msec.
- Negative throttle position change is less than 1.9 percent for 100 msec.