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?

 

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

 

mines doing the same. bad o2 sensor homie.

 

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

 

It's operating pretty much the same. If not a tiny bit better from the cold air. No weird idle or anything.

So bad O2 sensor? is there any way to test them?

 

its called free air calubration. un screw it, and turn the key to on. dont start the car.

with the sensor in the air, it should read a solid number. if not, then its the sensor.

 

+1 for recalibration.

 

Which wideband is it?

 

prosport gauge kit.

DUH! I totally forgot about recalibration. Thanks

 

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.

 

questionable reading from the wideband

 

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.

 

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.

 

if the O2 sensor is fouling out from idling then it's either a crappy wideband sensor or there is issues with the car like additives in the fuel or oil spewing onto the sensor.

 

I only let it do this once since it was really cold out. I don't have a heater so I was hoping some of the hot rotary air would melt the ice on the windshield.