zachg88vert

iTrader: (7)

i have a quick question about the pfc and an aem wideband o2. with the pfc it runs off stock sensors. will replacing the o2 sensor with a wideband o2 effect the pfc? thanks ~zach

phantom works

iTrader: (3)

You need to go into the commander and turn off the O2 feedback. the pfc doesn't care if you have an O2 sensor or not.
So basically you can run it 2 ways. with the stock sensor and the the PowerFC using the sensor or replace the stock sensor with the AEM UEGO and just turn off the O2 sensor feedback feature in the commander and the PowerFC won't worry about the stock sensor being there.
The commander owners manual tells you how to do this on page 36.

If you don't have the manual.... you go into the ETC section on the commander then select the 'Original Function Setting', scroll down to the O2 F/B control. Click the right arrow key to select enable or disable and use the up and down keys to disable.

This is also where you disable the seq turbo control if you are running a single turbo or if you went non-seq.

boostedfc3s

iTrader: (2)

You might want to research putting the wideband sensor in the stock O2 sensor location. I have the AEM wideband and the instructions say to put the sensor downstream from the exhaust port 36" or more for turbocharged engines. ( high egt's will burn up the sensor )

phantom works

iTrader: (3)

If you go to aemonly.com you will see that Stephan Papadakis shows how to install the AEM UEGO and uses his Drift S2000 racecar as an example and they installed the wideband O2 sensor no more than 6-8 inches from the turbo. I guess that AEM isn't to worried about the 36 inches.

I have mine mounted in the stock location and I know an employee of AEM who also has his wideband O2 sensor in the stock location on his FD. There are many other FD owners on this forum who use different wideband O2 sensors also in the stock O2 bung location.

I have an aftermarket downpipe that's heat wrapped, maybe that help's.

I guess my point is, AEM can't afford O2 sensor failure while on the track with their factory racecar. That could possibly lead to engine failure.
You don"t win championships that way, like they did with Tanner Foust and their 350Z.

Why they don"t heed their own warnings in the instruction manual, who knows?

boostedfc3s

iTrader: (2)

No **** huh ? That's some good to know info. I always thought the sensors were kinda delicate. Learn something new and different every day. Thanks .

arghx

iTrader: (3)

I have personally used the early and late production AEM widebands. The reason why they don't "fail" is because they are not sophisticated enough to detect inaccuracies. You'd be hard pressed to have an AEM wideband ever indicate that something is wrong.

Here is a perfect example. A friend of mine foolishly disconnected the AEM controller/gauge from the car but left the sensor in while the car was running. This is a huge "no-no" on any wideband because the heater is not working. Well, he drove it for several hundred miles that way and then plugged the gauge back in. It seemed to work ok, but when I compared it to a known good sensor it would randomly be off by .2-.5 AFR, even under closed loop conditions (around the 14.7:1 range) where widebands are most accurate.

I personally had an earlier production AEM wideband and the display went out within a few weeks. The middle digit of the LCD would not light up, and the the tech support gave me hell about sending it back. I had to complain to customer service before they gave me a new one. I ended up switching to the innovate. It is a pain in the *** sometimes, but I am much more confident in its readings considering that it uses free-air calibration just like factory-installed wideband systems.

All the Bosch wideband sensors work the same basic way (and many use the exact same LSU 4.2 sensor). If one brand of wideband system appears to fail more easily than another, it is because the controller is better at detecting inaccuracies, not because the sensor is somehow more durable. Just because a sensor does not have a catastrophic failure does not mean it's working like it did from the factory.

You should DEFINITELY put it 36" away from the turbo, on a rotary especially. You will have 1400-1600 degrees post turbo based on my own EGT tests. Those sensors are not designed to handle that heat. I had to locate mine farther back than that, right before my catback.

phantom works

iTrader: (3)

What makes the stock sensor able to handle those temps?

Do you have cats on the car with a working air pump?

I read a discussion on this very subject and the argument for having it closer is for a more accurate reading and quicker response from the wideband. the farther away and the reading is diluted, and if you are still running cats with a working air pump the 36 inches put's the O2 sensor after the cats which gives an inaccurate reading obviously leaner because of the airpump adding air to the mixture after combustion takes place.

BTW, I am not doubting your knowledge at all. I have just heard arguments both ways on the subject and from some pretty knowledgeable guys.

cewrx7r1

iTrader: (2)

The stock sensor is not heated.

If you want O2 FB to work, route the 0-1 v output to the ECU stock O2 sensor wire.
The 0-5 v will go to your gauge and DL.

DC circuits are so simple!

arghx

iTrader: (3)

Narrow band sensors work in a completely different way than wideband sensors. The oldschool 1 wire sensors on these cars just directly produce a voltage based on the presence of oxygen in the exhaust. They don't even have a heater or a controller (later 90s 4 wire narrowbands are heated to improve cold start emissions by getting up to temperature faster so the motor can enter closed loop).

Widebands operate by using a current pump (that is an oversimplification). The voltage they produce is an output generated by the controller (as it interprets the signal from the current pump) rather than the sensor itself. It's a lot more complicated and sensitive.

Nobody will tell you to put a wideband behind the cat if you can avoid it. That is only an unfortunate compromise if you are using a tailpipe wideband at a dyno. If you have no emissions like many cars on here I would suggest you put it right before the catback if you want it to last.