Wide band O2 sensor installed

[Dave WM]

Put a bung on the Z and installed. after warm up idle mix is around 12.5 ish, tried to lean more with the bypass screw but that was as lean as it would go, started at about 11.5 so I was able to bring up some. I did confrim TPS sensor was closed during the idle.

Drive around the block test results in mostly 13-13.5 with occasional blips into low 14's, but never sustained above 13's.

Will do some highway driving tomorrow just to base line it. I have a few AFM's to try out and see if there is any difference. I am sure at least one has been opened up so I will prob experiment with that one to see if I can get to an optimal lamba reading or a mix of 14.7 while steady cruising. This is a 75 with NO closed loop (no narrow band O2 sensor for the ECU to monitor. I assume without a closed loop capability its prob best to err on the side of rich vs lean.

I will get some videos later (or it never happened.....)

[Dave WM]

got a lot of drive time will post up videos later. All checked out very good. I was impressed by how well it managed the fuel air mix with no feed back. 

[Dave WM]

there are several, I tried to capture the reading under varied conditions.

 

[HusseinHolland]

So, the stock EFI does actually manage close to stoich on the highway? Or did you tweak the AFM settings to lean it out? I like having a WBO2, just to know what's actually going on, esp. under load conditions. I will add an AEM WBO2 to my 280Z, but that's going to happen when I do the VQ35DE conversion.

[Dave WM]

no tweeking other than to lean up the idle air bypass screw which IIRC only effects A/F mix at idle. I have some other AFM's I plan to test out, spares, just to see if they do any different.

[Yarb]

@HusseinHolland Without having to dig back in previous posts can you elaborate on the VQ35DE conversion? thanks Friend 

[HusseinHolland]

40 minutes ago, Yarb said:

@HusseinHolland Without having to dig back in previous posts can you elaborate on the VQ35DE conversion? thanks Friend 

I'm not sure I mentioned it on here yet. A neighbor who is also a car nut noted that a good friend of his up in RI has a 2006 350Z w/6 speed that will not pass inspection due to rust in the rear subframe. He suggested that I would perhaps be interested in the car to use as a donor. That is the ideal way to go, as I will have all the EMS, modules, etc., and everything else that I might need. The price he is asking is less than I would pay for a CD009 trans & VQ35DE motor, and he's going to deliver it in a couple weeks 🙂.

Apex Engineered makes a front subframe designed to properly locate the Nissan V6, so I will likely go that route & then fabricate whatever else I need from there.

[TomoHawk]

Sorry,  but there is still n such thing as an air-to-fuel ratio sensor.

Edited June 8, 2023 by TomoHawk

[Dave WM]

no such...

[chaseincats]

On 6/7/2023 at 11:14 PM, TomoHawk said:

Sorry,  but there is still n such thing as an air-to-fuel ratio sensor.

do NOT start this again.  you are wrong, you have been proven wrong on the previous 8 page thread 10 times over, all modern cars have this, you are wrong, stop spreading wrong information, go to autozone or even your favorite nissan or frankly any oem dealer and ask for an o2 sensor and they will give you one

 

stop.

Edited June 15, 2023 by chaseincats

[chaseincats]

On 6/2/2023 at 12:05 PM, HusseinHolland said:

So, the stock EFI does actually manage close to stoich on the highway? Or did you tweak the AFM settings to lean it out? I like having a WBO2, just to know what's actually going on, esp. under load conditions. I will add an AEM WBO2 to my 280Z, but that's going to happen when I do the VQ35DE conversion.

Yep, using an o2 sensor and an AEM air/fuel gauge I was able to get it to run stoich after the forum and I worked through this thread.  I was actually pretty astonished at how well it holds stoich at freeway speed as long as your TPS is set right - it won't hold it while driving around town, you kind of tune the AFM so that it runs stoich at highway speed (it will run richer around town by design and won't lean-out)

Here is how to do it:

 - get rid of ALL vacuum leaks using the hand pump and cigarette method

 - once you are SURE all are gone, run through the EFI bible and check all sensors to make sure they're in spec

 - once all your vacuum leaks are gone, your TPS is set correctly per atlanticz, lean the AFM back 3 teeth (counterclockwise) and it will run stoich at highway speed, sound/feel healthier around town, and smell more like a modern car

 - I'd HIGHLY recommend doing this with an air fuel gauge/o2 sensor so you can be sure your numbers are right, but if you do everything above, you should be good

Edited June 16, 2023 by chaseincats

[chaseincats]

On 5/26/2023 at 4:52 PM, Dave WM said:

Put a bung on the Z and installed. after warm up idle mix is around 12.5 ish, tried to lean more with the bypass screw but that was as lean as it would go, started at about 11.5 so I was able to bring up some. I did confrim TPS sensor was closed during the idle.

Drive around the block test results in mostly 13-13.5 with occasional blips into low 14's, but never sustained above 13's.

Will do some highway driving tomorrow just to base line it. I have a few AFM's to try out and see if there is any difference. I am sure at least one has been opened up so I will prob experiment with that one to see if I can get to an optimal lamba reading or a mix of 14.7 while steady cruising. This is a 75 with NO closed loop (no narrow band O2 sensor for the ECU to monitor. I assume without a closed loop capability its prob best to err on the side of rich vs lean.

I will get some videos later (or it never happened.....)

Try unplugging the TPS connector temporarily and see if it leans out