Hi, does anyone know what wire on the rear 02 sensor I would hook the sensor wire for a narrow band a/f guage? thanks oh it's an 06 sti
As long as nothing changed from 05.5 here is the ECU pinout for it. http://www.ravensblade.com/car/modifications/misc/wiring/05ImpSTI_ECM.pdf
waste of money! the rear O2 provides no useful information other thean the cat is working. Save your money and buy a wide band or download the tari software and monitor the front O2 which will give you more info but not as good as the wide band.
Both the front and rear are narrowband o2s why would the front give you any more information than the rear? And how would you tell the cat is working from one?
Sorry they are not both narrow bands. The rear is not use to do anyting except verify that there is a gradient difference from the front O2. This way the ECU verifies the Cats are working properly. The front O2 has a range from 11.0 to 25.0 AFR IIRC. Not a true wide band as most would go down to at least 8.0:1 but the ECU uses this sensor to control the car. If you were to unplug it the car goes into failsafe mode and throws 6+ codes. If you unplug the rear it throws 3 codes and the car runs fine.
So if the front o2 already goes to 11:1-25:1 why buy a wideband for the car? Why not just use that to tune with? I don't get why TurboXS would even think of making one when there's already one on the car. Unless, there's something that nobody's mentioned ie: still very inaccurate like a narrowband.
Actually the front only goes down to 12:1 and I would say that it is not the most acurate way to tune your car. You can use it for light loads and low boost (6-8psi), but anything past that you will be richers than 12:1 and the front is useless. Russ
The front sensor is accurate in a bell curve with the best readings around Stionch where the ECU trys to run the car in closed loop.That is all the closed loop fueling needs to run the car once it crosses into open loop it is on the map table and runs from there. Seeing as subi's come from the factory running high 9's low 10's in open loop how would you know what AFR the car is at if the stock sensor only goes to 12? I think you need to spend some serious time in the engine management forum in NASIOC. :lol: Thanks Russ, it has been a long time since I looked at a log from DD or Tari
