Hi,

I installed an AFR meter, (the 10 led kind that connects to the factory O2 sensor) this weekend. The readings I'm getting are not what I expect to see:

1. The meter takes at least 20 minutes from startup for the readings to start changing.
2. I only get a max of about 5 lights (stoichiometric) yet I would expect to see at least 8 lights (rich).

I'm tending towards the opinion that maybe the O2 sensor is not working so well, maybe it's heater circuit is not working.

Before I get under the car to check, can anyone with an AFR meter tell me what kind of readings they get? Specifically, how long does it take to reach the point where the lights start flickering as you get on and off the accelerator and how many bars do you get at full acceleration?

BTW the car is a MY95 WRX.

 

Bump

There must be someone on SN with a narrowband AFR meter that can reply.

 

Sounds to me like your sensor is faulty , I would expect a small period of inactivty from start up but not 20 mins...

 

sensor is dead. they become slow to start working, and will die off once reasonably hot. Not unusual on a 95wrx, new genuine sensor at £170 is the one to get, or move the sensor to the top of the downpipe (if decatted) and fit the later one at around £110.

 

Thanks a bunch for the replies guys. I'll have it replaced tomorrow. Hopefully I'll see a reduction in my fuel consumption as well.