RomRaider

In principle you are right but unfortunately combustion is not very nice in lean mixtures. Nitrous Oxide compounds become greater and the air-gas mixture burns hotter which is not so good for your engine. Basically you want to get as close to stoichiometric as possible for 'efficient and safe' performance.

This may be a very stupid question but, can the front O2 sensor be unplugged resulting in constant open loop?

Yes.
And you will also get the CEL light on and probably limp mode too.

hmmm. CEL is easily dealt with. Limp mode maybe not

I need to disable closed loop because I don't have a front o2 sensor installed in my new twinscroll manifold (will get it welded to the dp at some point)

To get the car on the road though i want to disable CL.

But am unclear on the following:

Do I zero all of the CL to OL transition and CL Delay values, incl. CL to OL Transition Counter Step (MAF Value) which "warns" the user not to set it to 0? Or do i just zero the CL to OL transition parts?

Then do I also need to zero the Closed Loop Front Oxygen Sensor Scaling, compensation and target compensation tables?

Would appreciate any help you guys can give me.

Thanks!

You can leave the sensor scaling, compensation, etc, unchanged.

I don't know about the MAF counter... I suspect that it's just not preset in my ROM. Or maybe it was added to the definitions relatively recently. Hopefully someone else can shed some light on it.

I think theres a step missing here in the original post saying to change the 14.7 values to 14.6.

Hi guys,

Ok so I have done this procedure but it seems I can't get out of ''CL/OL 7 status'' which has something to do with the ECT. (yes the car is fully warmed up).

Also, should I rescale my MAF because it seems I can't reach the targeted AFR in open loop...I am waiting on my wideband to arrive but the stock O2 seems to read pretty good (not lower than 11.14 though) I am not sure about the MAF rescaling thing because im only running a turboback with the OEM intake...

Help would be much appreciated since I've read bad noodle's complete tuning guide and the access tuner tuning guide also and still don't know how to set the open loop fueling in the ballpark.

hi,

i tried and my CL/OL status also at 7...MAF scaling required to rescale

i installed AEM wideband at my downpipe and compare the AFR reading, the stock one vary quite alot compare to AEM.

when logger show 14.7AFR, my AEM is bout 16AFR. my 4th cylinder is misfire as shown in logger.i rescale the MAF scaling until AFR at idle bout 14.5(AEM reading)..engine stable n no more cylinder misfire shown in logger.

Is it possible to just delays the zero and set Minimum Active Primary Open Loop higher than 14.7?

I am wondering if you disabled tip-in to try to get the MAF scaled properly, is this going to cause problems with running super lean if you were pretty light on the throttle?

I left tip-in active, and was gentle with the throttle. You have to stab the throttle pretty abruptly to trigger tip-in anyhow, at least on my car.

Also, I strongly suspect that disabling it would make the data more noisy, not less, unless it's way way off.

NSFW can you help me out?

1) My rom doesn't have "Minimum Active Primary Open Loop Enrichment" documented .

2) I tried setting my 14.7's in the open loop fueling tables to 13.9 and when I ran the car it still targeted 14.7 until I hit open loop which seems to happen at the "CL delay maximum engine speed".

Do I need to 0 out all of the other delay tables also? I'll try lowering the CL delay maximum engine speed limit.

Which ROM do you have? And what model/year?

It could just be missing from the definition, or it could be the that the transition to open loop just works differently in your car. With my 05, there's just one "CL to OL Delay" value that needs to be set to zero, but I wouldn't be surprised if things got more complex in more recent cars. I guess I'd try setting ALL of the delay values to zero and see how it behaves then.

On the BRZ the value is set to 14.0 by default but you want it to be in closed loop around idle and startup. I found if not the ECU doesn't properly switch out of the startup mode into full CL or OL.