Technical Paper
The Effect of Intermittent Engine Misfire and Air to Fuel Ratio Excursions on Exhaust Catalyst Temperature
1994-03-01
940927
The effect of ignition induced misfire on exhaust catalyst temperature has been investigated using an engine bench and a computer model. The effects of misfire rate, exhaust gas flow rate and catalyst condition are reported and conditions that would lead to the melting of a ceramic catalyst are predicted. The modelling techniques have been extended to predict the effect of a fast air to fuel ratio transient on catalyst temperature. Measurements of catalyst temperature during a simulated deceleration using fast response thermocouples have shown that a short lived temperature increase does occur.
