AFR at idle??
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From: Frederickburg, VA
AFR at idle?? I've finally got my LC-1 installed and logging in hpt. I've got it wired directly into the PCM through EGR. Can someone help me understand if what I'm seeing is normal, or needs to be adjusted.
While at idle I'm seeing AFR between 14-22 I give it a little gas and is seems to be in the range of around 14-16. I don't have any other readings as of yet because I didn't have it working at the track this past weekend. I notice my AFR in hpt only goes up to 18, I'm assuming that's because I programed the LC-1 from 0v 10:1 & 5v 18:1. Should I modify this to maybe 22:1 at 5v and then modify my formula in hpt? Thanks.
-Bryan
While at idle I'm seeing AFR between 14-22 I give it a little gas and is seems to be in the range of around 14-16. I don't have any other readings as of yet because I didn't have it working at the track this past weekend. I notice my AFR in hpt only goes up to 18, I'm assuming that's because I programed the LC-1 from 0v 10:1 & 5v 18:1. Should I modify this to maybe 22:1 at 5v and then modify my formula in hpt? Thanks.
-Bryan
Last edited by NVE THIS; Mar 22, 2007 at 08:51 AM.
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From: Frederickburg, VA
Originally Posted by brad8266
Are you cammed? I wouldnt worry about AFR at idle as long as its not running rich. Lean idle is good.
so looks like I need a new one now.I can't do much tuning until I get a new DS, but want to get things toghether so I can have hpt ready to get my car the way it should be. I also have a 150 N2O shot I'll be running, but I'm going to get a good N/A tune. Thanks for any help.
-Bryan
Originally Posted by Flipn
I thought Idle should be averaging @ 14.7 (or atmospheric pressure) of course it will vary but i thought that is the target AFR..
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From: Frederickburg, VA
Originally Posted by SSpdDmon
If the car had a stock cam that didn't introduce fresh air into the exhaust via overlap, then yes, 14.7 is what you want to target. But, he's cam'd so it's a little different.
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Originally Posted by SSpdDmon
It means that if you want the car to operate in closed loop, it's going to idle rich. If you don't want it to idle rich, you need to trick it into open loop for idle.
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From: Frederickburg, VA
Originally Posted by SSpdDmon
It means that if you want the car to operate in closed loop, it's going to idle rich. If you don't want it to idle rich, you need to trick it into open loop for idle.
But looking at my idle AFR, it looks like it's lean, right? 
Originally Posted by Flipn
I thought Idle should be averaging @ 14.7 (or atmospheric pressure) of course it will vary but i thought that is the target AFR..
Originally Posted by 98SS2836
My car cold idle's around 20 to 1. I can't remember what the hot idle is because it's still winter.
Originally Posted by SSpdDmon
Are you sure that's not the WBO2 just warming up? It sounds a little hard to believe it will idle ok while being that lean.
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From: Frederickburg, VA
Originally Posted by shoemike
do you have the sensor on one side of the exhaust?
i had to move my wide band to the cat back
because of the fluctuations i was getting.
i had to move my wide band to the cat back
because of the fluctuations i was getting.
Originally Posted by kamikazematt
sorry to bring up the old. but how do you "trick" it to open loop at idle? i've been having some problems idleing rich.
SSpdDmon describes a way to do it in that thread.
R/
Frat
