AFR's are all over the place
#1
AFR's are all over the place
So today I took teh 7 out for work. I let her sit + warm up for about 15 min. When I got in my AFR gauge was blinking 20 (meaning it's over 20) Normally it's around 14-16 at idle when it's warm. Then while I was driving, I noticed that it was going all the way down to 10! Holy crap! I noticed it was at 0 PSI as well. So I just took it easy. Today it's a bit colder than it has been, about 38* or so.
91 TII swap
CS downpipe + test pipe
apexi N1
pro sport gauges
custom TID
No fuel control
stock injectors that were supposedly cleaned right before I bought the motor.
Is it a boost leak? What do you think?
91 TII swap
CS downpipe + test pipe
apexi N1
pro sport gauges
custom TID
No fuel control
stock injectors that were supposedly cleaned right before I bought the motor.
Is it a boost leak? What do you think?
#2
Sharp Claws
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was it idling strangely when your wideband was reading 20:1 AFR? am i wrong in assuming it is a wideband correct?
i ask because there is almost no way a rotary can still properly run while so lean in the AFR range, ~17's are about where it will want to stall out regardless of ambient conditions.
so basically i think your wideband O2 sensor/wideband driver is going wacky
i ask because there is almost no way a rotary can still properly run while so lean in the AFR range, ~17's are about where it will want to stall out regardless of ambient conditions.
so basically i think your wideband O2 sensor/wideband driver is going wacky
#4
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if you have the air pump and ACV hooked up you might see 20:1, it should idle @16-18:1.
remember the air injection is to the exhaust ports, so the o2 will be lean.
if you took the air pump and acv off, then 20:1 is a bad o2 or a rich misfire
remember the air injection is to the exhaust ports, so the o2 will be lean.
if you took the air pump and acv off, then 20:1 is a bad o2 or a rich misfire
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#10
Banned. I got OWNED!!!
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I personally do not trust the Prosport gauges, just seen too many issues with them.
A lot of times when your wideband goes wonky it is the power/ground setup, so double check your wiring. The Prosport uses the Bosch 4.9LSU sensor, which is different than the more common (and probably more reliable) 4.2 or NTK sensors. How long have you had the gauge and sensor installed? Wideband sensors indaily use should last around 70k miles, unless you are using leaded gas regularly, like weekly, which will shorten the life of the unit. If you have the sensor mounted too close to the exhaust outlet, especially in a rotary, that can also effect the life of the sensor, so doble check that too.
Personally I would replace the Prosport with an AEM "analog" faced wideband and hook it up exactly as the directions say.
A lot of times when your wideband goes wonky it is the power/ground setup, so double check your wiring. The Prosport uses the Bosch 4.9LSU sensor, which is different than the more common (and probably more reliable) 4.2 or NTK sensors. How long have you had the gauge and sensor installed? Wideband sensors indaily use should last around 70k miles, unless you are using leaded gas regularly, like weekly, which will shorten the life of the unit. If you have the sensor mounted too close to the exhaust outlet, especially in a rotary, that can also effect the life of the sensor, so doble check that too.
Personally I would replace the Prosport with an AEM "analog" faced wideband and hook it up exactly as the directions say.
#12
I haven't had any problems with any of my other prosport gauges.
It's been in there maybe 3k miles over a year. I don't drive teh 7 much anymore.
Location of the o2 sensor itself is at the middle of my corksport downpipe. I moved it far back because of the heat of the rotary.
It's been in there maybe 3k miles over a year. I don't drive teh 7 much anymore.
Location of the o2 sensor itself is at the middle of my corksport downpipe. I moved it far back because of the heat of the rotary.
#13
Engine, Not Motor
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You might also be fouling out O2 sensors by letting your car idle for 15 minutes...Just a thought. No need to let it warm up. Just start it, put on the seatbelt and drive.
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