how much boost?

[Dragon Humper]

Are you talking inspection requirement or what is actually there. I can assure you that all fuel injected vehicles from 1982 on has both an O2 feedback and a CAT to satisfy emissions requirements. In Japan they went as far as about 1995 with carbs on the KEI engines, but they definately had a CAT.

If you have a 100% stock ECU and no O2 sensors are being used then you will have the SIL light on (check engine). If it is not then you have a Nistuned board or the light is burned out. Not sure if the ECU will go into limp without the O2 info.

I am willing to bet that there is only me and about 1or 2 other dudes in North america that are driving their street cars with no O2 feedback.



Jon.

[floydispink]

Are you talking inspection requirement or what is actually there. I can assure you that all fuel injected vehicles from 1982 on has both an O2 feedback and a CAT to satisfy emissions requirements. In Japan they went as far as about 1995 with carbs on the KEI engines, but they definately had a CAT.

If you have a 100% stock ECU and no O2 sensors are being used then you will have the SIL light on (check engine). If it is not then you have a Nistuned board or the light is burned out. Not sure if the ECU will go into limp without the O2 info.

I am willing to bet that there is only me and about 1or 2 other dudes in North america that are driving their street cars with no O2 feedback.



Jon.

I'll take that bet

[Dragon Humper]

Then you are going to have to elaborate more on your setup.



Jon.

[Skym]

I don't have o2 sensors, but thanks for all the input

You're welcome. Oh, ok. Stock R32 GTR ECU has 2x o2 sensors. Stock ECU can run in open loop without o2 sensors (have done that on my car for a while) and stock ECU does ignore o2 sensor input initially when engine is warming up. Closed loop is with o2 sensors active.

[Bruizer]

I had planned on running no 02 feedback but the direct port egt controller and sensors were too much so I went dual egt and dual channel wide band instead.

How do you run without 02? Egt?

[Skym]

It's easy as turning off the o2 feedback via tuning software or unplugging o2 sensor. But you'll need to check tune afterwards via wideband to make sure there's no problems o2 sensor is compensating for. Also stock o2 sensor is ignored by stock ECU (goes into open loop) when engine is on boost. It's only a narrowband 0-1V sensor. Wideband is 0-5V.

[Dragon Humper]

Thats right...and if her ECU is 100% stock then she should be getting the SIL lamp coming on when the motor is supposed to be going into closed loop. If not, then the light is either burned out or the ECU has been altered to ignor the O2 altogether.


I am curious though how the stock ECU even knows that it is in boost with no MAP sensor, I will never understand why Nissan didn't include one when even the knuckle dragging Americans were using them on the Grand National 5 years earlier.





Jon.

[Skym]

Very simple setup. There's a selected area on fuel map (can turn this selected area on in tuning software to see if ECU is looking at o2 sensor) where the stock ECU looks at o2 sensor input. Once outside that area (usually the area of fuel map where engine is on boost) the stock ECU ignores the o2 sensor input and looks at the fuel map only.

Turning off o2 sensor feedback makes ECU look at fuel map only, ignore o2 sensor input in that selected area. Each ECU is different in how you do this (turn off o2 sensor feedback).

If were to have a German made car, some of them run Bosch wideband sensors stock (same Bosch sensors as used on aftermarket widebands).

[Dragon Humper]

Thats interesting...I would have bet money that the MAP sensor that they used to supply the boost guage with info would have also been used as a switch to tell the ECU that. I even looked through the wiring diagrams to see if that was true or not...but no.

At any rate...whats the deal on your ECU? There is no way you are running O2-less without the check engine light coming on.



Jon.

[Skym]

No engine check light coming on. o2 sensor voltage stayed at one value (can monitor it via turbo timer), so obviously ECU was using a preset value when o2 sensor was unplugged (same thing it does when MAF's are unplugged).