Open loop AFR on cold start
#1
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It seems that when I tune the car with the fuel trims and get my VE around idle really close, plus or minus 5%, the car is lean on cold start up. The way around it that I have found is to play with the open loop equation table in these KPA/RPM areas to richen it back up, so that when it warms up and goes into closed loop all is good. It seems to be working OK but just wondering if there is something I am missing.
#3
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Cold start AFR ought to be set by "what it likes", not
a wideband number. Stoich (indicated) may not be a
valid target, esp. if fuel atomization is poor, AIR pump
is on, whatever. Go by the vacuum reading (MAP
inverse) as your indicator-of-happiness as you mess
around.
a wideband number. Stoich (indicated) may not be a
valid target, esp. if fuel atomization is poor, AIR pump
is on, whatever. Go by the vacuum reading (MAP
inverse) as your indicator-of-happiness as you mess
around.
#5
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Cold start AFR ought to be set by "what it likes", not
a wideband number. Stoich (indicated) may not be a
valid target, esp. if fuel atomization is poor, AIR pump
is on, whatever. Go by the vacuum reading (MAP
inverse) as your indicator-of-happiness as you mess
around.
a wideband number. Stoich (indicated) may not be a
valid target, esp. if fuel atomization is poor, AIR pump
is on, whatever. Go by the vacuum reading (MAP
inverse) as your indicator-of-happiness as you mess
around.