Method for controlling an engine to obtain rapid catalyst heating
First Claim
1. A method for controlling an engine have at least first and second groups of cylinders, the engine coupled to an emission control device, comprising:
- in response to engine starting;
operating the first group of cylinders at a first ignition timing and rich of stoichiometry; and
operating the second group of cylinders at a second ignition timing more retarded than said first group and lean of stoichiometry.
3 Assignments
0 Petitions
Accused Products
Abstract
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
109 Citations
6 Claims
-
1. A method for controlling an engine have at least first and second groups of cylinders, the engine coupled to an emission control device, comprising:
in response to engine starting;
operating the first group of cylinders at a first ignition timing and rich of stoichiometry; and
operating the second group of cylinders at a second ignition timing more retarded than said first group and lean of stoichiometry. - View Dependent Claims (2, 3, 4)
-
5. A method for controlling an engine have at least first and second groups of cylinders, the engine coupled to an emission control device, comprising:
in response to engine starting;
first transitioning to;
operating the first group of cylinders at a first ignition timing; and
operating the second group of cylinders at a second ignition timing more retarded than said first group;
second transitioning to;
operating the first group at said first ignition timing and rich of stoichiometry; and
operating the second group at said second ignition timing and lean of stoichiometry. - View Dependent Claims (6)
Specification