a/f ratio question. Yes, I searched.
#26
The Silent but Deadly Mod
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RX-7's fuel cut on lift-off decel.
Is your air pump working? Your idle rpm seems really rich. Unless your quoting AFR's that occur after you've stopped the ACV from dumping air near the O2 sensor. If that's the case, then it's fine.
For idle, I normally lean out the fuel until the engine starts to stumble, then raise it to the lowest level possible without stumbling. The side effects are sometimes the engine will stall on hot starts due to the excessive lean, so you have to feather the throttle until the car stabilizes itself. I've never stalled the car from clutch-in though.
Is your air pump working? Your idle rpm seems really rich. Unless your quoting AFR's that occur after you've stopped the ACV from dumping air near the O2 sensor. If that's the case, then it's fine.
For idle, I normally lean out the fuel until the engine starts to stumble, then raise it to the lowest level possible without stumbling. The side effects are sometimes the engine will stall on hot starts due to the excessive lean, so you have to feather the throttle until the car stabilizes itself. I've never stalled the car from clutch-in though.
#27
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Glad to hear that lean on decel is normal. I figured as much.
The air pump is working, and AFR's are with it functioning. Yes it is very rich now. I checked it out on my buddies exhaust analyzer hydrocarbons at 1600 (ppm) at 850 rpms and anywhere from 130 to 95 (ppm) at 2500 rpm's. Exchange rate of converter is pretty low also.
The air pump is working, and AFR's are with it functioning. Yes it is very rich now. I checked it out on my buddies exhaust analyzer hydrocarbons at 1600 (ppm) at 850 rpms and anywhere from 130 to 95 (ppm) at 2500 rpm's. Exchange rate of converter is pretty low also.
#28
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my stock AFR's were in the 17's at idle, thanks to the ACV dumping air near the O2 sensor.
I've never done this on a turbo, but on my two NA's, I turned down the fuel at the idle rpms until it stumbled, then raised it 1 notch. You may want to try that and see how it is.
I've never done this on a turbo, but on my two NA's, I turned down the fuel at the idle rpms until it stumbled, then raised it 1 notch. You may want to try that and see how it is.
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arghx.....I haven't recalibrated yet.
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Yeah its an S5. So why would it be running so rich at idle? Yes I can lean it out with safc. But it shouldn't be that rich in the first place. Unless a streetport, which it has, would cause this. Which I could see it might as overlap is increased.
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