Idleing @ 18-19 AFR is this Right?
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From: Shelby Twp. Mich
Idleing @ 18-19 AFR is this Right? I just got my wide Band Hooked up.What AFR Should be at Idle?I have a 408 with a 244/248 Cam.I am Idling Between 18.5 and 19.0 is this Right? Thanks
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From: Shelby Twp. Mich
Yes I did it per the directions 2 times just to make sure and both times were the same.I thought 14-15ish was right.My Tune is an openloop tune.Should I dial it in with the OLFA Table?Thanks
cam overlap Another thing also,
If you have cam overlaping, you'll get a lean idle reading with the wideband O2! It's reading the oxygen escaping the combustion chamber during the overlap.
Thing is, if it will idle smooth on 18.5 to 19 afr, and your off idle transaction is smooth, then I'd save the gas and let her ride.
Now cruising around, I'd richen it up to 14.5 to 16 afr. Accleration, I'd defintely richen her up to around 12.5, flatlining WOT around 12.9 to 13.2.
That's just saving gas at cruise and idle.
D Moss
If you have cam overlaping, you'll get a lean idle reading with the wideband O2! It's reading the oxygen escaping the combustion chamber during the overlap.
Thing is, if it will idle smooth on 18.5 to 19 afr, and your off idle transaction is smooth, then I'd save the gas and let her ride.
Now cruising around, I'd richen it up to 14.5 to 16 afr. Accleration, I'd defintely richen her up to around 12.5, flatlining WOT around 12.9 to 13.2.
That's just saving gas at cruise and idle.
D Moss
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From: Shelby Twp. Mich
I did gas it a little by hand and it did come up to 14-16 not hitting gas hard though.Idle is good and doesnt do any stumbling on excel or decel.Reving engine up in Nuetrol she comes back to Idle fine.Idling like this ,Can it cause an extreme smell of Fuel?Damn I mean it makes my eyes burn....
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From: Shelby Twp. Mich
I dont know what it is cruising around yet.I wont know that until spring.This problem is what made me put it away for winter in the firstplace.The damn thing floods out from trying to start it from 50 degrees and lower and will not start.
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Try turning it off with the VCM controls and see what happens. 
Also, is this happening from a cold start up to 180 ish or is it happening after the car has been run and then restarted? If the later, it could be a heatsoaked IAT sensor. It is a known condition and should richen up after the IAT cools back down to the actual Intake air temp. I put a resistor in my IAT sensor plug that reads 64* all the time. No more problem. Now I live in Florida and my intake air temp is usually within 30* from summer to winter. Good luck.
Is the VE table dialed in? If not, you have to add to the VE table values in the idle area. Are you logging AFR thru HPT? If you are not because you dont have the IO (Pro version) there are a few good write ups on how to log thru the EGR and a couple of other sensors. Do a search. I am logging mine thru the EGR and it made tuning soooooo much easier.