Post by Stinger on Jul 12, 2011 12:43:59 GMT -5
As provided by WesK:
I pay no attention to lambda (AFR) values for afterstart. Prior to tuning afterstart, your warmup enrichment tables need to be dialed in (as those values are also factored in). If (after it is already running for 20 seconds or so) you are happy with the way the engine runs while in warmup mode you can move on to the Afterstart values. When I ask do you understand the strategy, I don't mean how to adjust it, I mean how it works.
There are several components to the starting and afterstart stategy:
1) Cranking fuel PW vs. coolant temperature. When cranking the engine (as defined by rpm<cranking rpm setting) this AND ONLY THIS defines how much fuel is injected. Adjust this if the engine doesn't "catch" quickly at a given coolant temperature. If the engine "catches" rather quickly and then dies, move on to afterstart enrichment.
2) The afterstart enrichment is the additional fuel (expressed as a %) that is added in addition to the normal running and warmup table adjusted fuel. Increase and decrease this value and see how the engine responds. Typically if the engine runs for a few seconds and then dies it needs more. If it dies immediately after "catching" it likely needs less.
3) How long the afterstart enrichment is applied is defined in the ASE taper table. This is expressed in cycles. At time = 0 (as defined by the instant RPM exceeds cranking rpm) ASE fuel is equal to the full ASE amount. At time= ASE taper table value no additional fuel is added based on afterstart (and only the warmup fuel vs. coolant temperature is added). If the engine runs for several seconds afterstart and then dies, try increasing the taper time.
I pay no attention to lambda (AFR) values for afterstart. Prior to tuning afterstart, your warmup enrichment tables need to be dialed in (as those values are also factored in). If (after it is already running for 20 seconds or so) you are happy with the way the engine runs while in warmup mode you can move on to the Afterstart values. When I ask do you understand the strategy, I don't mean how to adjust it, I mean how it works.
There are several components to the starting and afterstart stategy:
1) Cranking fuel PW vs. coolant temperature. When cranking the engine (as defined by rpm<cranking rpm setting) this AND ONLY THIS defines how much fuel is injected. Adjust this if the engine doesn't "catch" quickly at a given coolant temperature. If the engine "catches" rather quickly and then dies, move on to afterstart enrichment.
2) The afterstart enrichment is the additional fuel (expressed as a %) that is added in addition to the normal running and warmup table adjusted fuel. Increase and decrease this value and see how the engine responds. Typically if the engine runs for a few seconds and then dies it needs more. If it dies immediately after "catching" it likely needs less.
3) How long the afterstart enrichment is applied is defined in the ASE taper table. This is expressed in cycles. At time = 0 (as defined by the instant RPM exceeds cranking rpm) ASE fuel is equal to the full ASE amount. At time= ASE taper table value no additional fuel is added based on afterstart (and only the warmup fuel vs. coolant temperature is added). If the engine runs for several seconds afterstart and then dies, try increasing the taper time.