AFR At Cruising
#1
AFR At Cruising
On the innovate forums I read that a 15.2-15.4:1 AFR will be ideal to improving fuel economy when cruising. This is according to Klaus the engineer who answers questions on the forums.
When I am cruising my AFRs are 14.3-14.8. How can I achieve a 15.2-15.4 AFR when cruising? Do I change the load values on the MAF table below load point 25? How much fuel should I take off below load point 25?
Thanks
When I am cruising my AFRs are 14.3-14.8. How can I achieve a 15.2-15.4 AFR when cruising? Do I change the load values on the MAF table below load point 25? How much fuel should I take off below load point 25?
Thanks
#3
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At cruise your car should be in closed loop, which means that changing settings on the XEDE tables will have no effect. The only way to affect closed loop fuel trims would be by fooling the ECU into thinking that 15.2-15.4 AFR is stoich. This can be done by using the LM-1 or LC-1 to simulate the stock narrowband O2 sensor, since you can adjust the voltage the LM-1/LC-1 supplies as its narrowband O2 signal.
heyzeus, unless you have adjusted the lambda multiplier in your wideband, you'll still read ~14.7 even with 10% ethanol...
l8r)
heyzeus, unless you have adjusted the lambda multiplier in your wideband, you'll still read ~14.7 even with 10% ethanol...
l8r)
#6
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Originally Posted by nj1266
I was told that running at 15.2-15.4:1 at cruising would improve fuel economy the most and it will not have any ill effects on the car. If that is the case, then why not do it.
Note that EU VW GTI's have a lean-run mode, but it works completely differently. They are able to run like 65:1 AFR, but fire their injectors during the compression stroke.
d