low throttle tuning..

[derK]

So let me get this straight with your help. The ECU controls all fuel maps under 75% throttle thus meaning that any changes to the SAFC at LOW THROTTLE settings are basically useless?? and on the SAFC i should have the low throttle at 74% and high throttle at 75 %??

so if that makes sense, all we really need to do to get a stoich reading at idle is to get the timing correct and the correct fuel pressure yes??

so in the end all we really need to tune is high throttle??

Thanks.

 

[tissimo]

ecu controls fuel maps up to 100% throttle..

 

[derK]

my bad....i meant to say closed loop and open loop. Closed loop is up to 75% throttle and open loop is 75% +??

so it is useless to make any changes in a closed loop setting since the ECU will just adjust those settings back to where it wants??

 

[tissimo]

no its not useless... but yes the ecu will learn its self back to 14.7 a/f in closed loop

 

[dbsupra90]

my bad....i meant to say closed loop and open loop. Closed loop is up to 75% throttle and open loop is 75% +??

so it is useless to make any changes in a closed loop setting since the ECU will just adjust those settings back to where it wants??

yes any changes you make in closed loop the ecu will counteract. hook up the Vf wire so you can see what the ecu is doing. that can be helpful in part throttle tuning. i usually make small corrections to get it as close to 2.5v as possible so the ecu changes as little as possible. seems to make better response and drivibility.