V1 Mikes Extended, Full Frame Goblin - 2009 Cobalt LS with 135k donor

[KSLunsfo]

The wideband should be about 18" away from the head. Too close and it burns up, too far and it responds slow.

I know I've seen this recommendation with aftermarket WBs and I swear it still surprises me. The LNF has a wideband literally about 6 inches away from the exhaust side of the turbo. Far as I can tell my ~90k mile engine o2 sensor is the original. Perhaps this starts to become an issue for higher intensity racing like road course where you're in the throttle for very long continuous amounts of time....??

 

[Desert Sasqwatch]

The second o2 isn't needed for the cat to function, only to know when the cat isn't functioning correctly, at least on GM. Of course it's needed to pass most emissions testing.

Again, my point for the ECU to know the cat is functioning it has to see the exhaust gas content before and after the cat. I've stated this 3 times now - if this is not correct please provide a cited source that states otherwise.

And as is expressed in numerous articles that can be easily found on the internet the ECU will make air/fuel adjustments based on the information it receives back from the O2 sensors - mainly the upstream.

 

[Gtstorey]

Again, my point for the ECU to know the cat is functioning it has to see the exhaust gas content before and after the cat. I've stated this 3 times now - if this is not correct please provide a cited source that states otherwise.

And as is expressed in numerous articles that can be easily found on the internet the ECU will make air/fuel adjustments based on the information it receives back from the O2 sensors - mainly the upstream.

Point was just added for clarification. First time you said for cat to function with the ECM it needs both. Depending on how you read that, it could be incorrect. Second time was a little harder to misinterpret, but still possible.
And GM uses ONLY the front o2 sensor for fuel control. I don't know about other OEMs.

 

[mike_sno]

Well, I think I do the following, my o2 sensor has 2 programmable analog outputs. I'll wire one for the wideband tuning (ac pressure arbeite input) and one for the ECU. That solves the issue with welding bung as well. Meanwhile I adjusted some of the settings and got the long and short term fuel trims way better dialed in (was in the+20 area) more I'm close to 0. Fairly happy achieving that with just a narrow band.

 

[mike_sno]

Really? I may grab one of those on my next order. Right now, it’s me pressing down the pulley and Mrs. Slipping the belt on.

If you want I throw another 2x6 on my mill. It does the trick.

 

[mike_sno]

Has anyone ever tried what happens if you set the programmable output of a wideband up to feed the ECU with a wider afr ratio?

 

[Ross]

The P12 ECU on an ecotec LSJ only wants to know if the O2 sensor is above or below stoichiometric. It doesn't care by how much.
The wideband O2 information is useful for tuning, but not needed for a properly tuned engine.

 

[Gtstorey]

What is the output of the wide band to feed to the ECM?

 

[mike_sno]

Seems like fully adjustable.

 

[Gtstorey]

Sounds like it can be made to work at least to some extent. There is enough question about the accuracy of aftermarket widebands on HPT forum that I would not adjust anything but wot based upon the wideband. And then put the OEM narrow band back in after that, unless your trims pretty much stay where they are with the WB.

 

[mike_sno]

I believe it. To be honest, I think this is all way less important that people think of. It's better than nothing and for sure helps to get the last bit of performance/efficiency out of a car. The fact that a narrow band dances around stoich makes me believe that this range is ok to operate the engine in, otherwise, i am sure it would have been changed. The fact that the engine switches in some cases to open loop and ignores some of the sensors it has is another indicator for that. Since I getting more and more my hand around engine tuning, I am less interested in an aftermarket ECU. I thought at the beginning, this would be great and gives you way more options,... but besides the E85 capabilities I am not missing to much.

And for E85 I may go the route of a second tune and flash the ECU if I change gasoline.

 

[mike_sno]

Made some redneck tow adjustment at my rear axcle, while I am getting prepared for the string method.

Gave it 360deg turn on the rear rods. Much much more stable now!!

 

[Gtstorey]

I believe it. To be honest, I think this is all way less important that people think of. It's better than nothing and for sure helps to get the last bit of performance/efficiency out of a car. The fact that a narrow band dances around stoich makes me believe that this range is ok to operate the engine in, otherwise, i am sure it would have been changed. The fact that the engine switches in some cases to open loop and ignores some of the sensors it has is another indicator for that. Since I getting more and more my hand around engine tuning, I am less interested in an aftermarket ECU. I thought at the beginning, this would be great and gives you way more options,... but besides the E85 capabilities I am not missing to much.

And for E85 I may go the route of a second tune and flash the ECU if I change gasoline.

What part do you think is less important? And of course dancing around stoich is ok for the range that the OEM uses that for.

You probably won't be able to pass emissions testing without the narrowband in place. Depends on how deep they dig.

 

[mike_sno]

What part do you think is less important? And of course dancing around stoich is ok for the range that the OEM uses that for.

You probably won't be able to pass emissions testing without the narrowband in place. Depends on how deep they dig.

Well, I think a sensor which is in an environment like the O2 sensor, covered with soot,... I am not quite sure how O2 sensors work, but I have my doubt that there is on the sensor side a reason why they only produce 0 or 1V, if lean or rich. There is for sure some sort of cheap electronic in the sensor itself. The ECU itself has already an analog input and it would not be a big deal to read more than just 0 / 1 from that signal.

Than the fact that sometimes the engine runs completely without the sensor. The fact that even the distance where to measure it, is not really something which is standardized ( this is part of deadtime,...) The complete set up seems to be simplified as much as possible and the tolerance band seems to be rather wide. Otherwise we would see different technology used.

 

[mike_sno]

Finished the wheel alignment yesterday. The string method works actually quite good and it doesn't even take long. I think it took me 45min for Steering and toe.

I have 0.5degree to in front and back and my steering wheel is now dead center

The car drives soooo much better! Unbelievable. On a interstate ramp I can let the steering wheel lose and it continues to turn. This is very interesting, I like it.

I still have a little instability if I get off wot at higher speed, but that is way way better than before.

I measured the camber. I have negative chamber around 1-2 degree at all wheels. Will do that next.

I also noticed that the profile on my rear tires does not have this sharp edge anymore in one direction.

 

[Gtstorey]

I think a vehicle with no return to center on the steering is dangerous. I would add more castor.

 

[mike_sno]

I think a vehicle with no return to center on the steering is dangerous. I would add more castor.

I have to test it on a regular curve/ straight. The interstate entries here in south florida are nascar stile with quite some angle to it due to the amount of rain we get.

 

[mike_sno]

I tried to get the cruise control working. I added a 6Ohm resistor parallel to the 3rd braking light. While driving, if I switch the CC on and push the set button CC does not work. Every now and then I see for a short moment Cruise Control Enables in the Display, but it is like super super short. Then it does away to whatever display I had before ( usually coolant temp ).

What are the conditions that CC can be enabled?

 

[Gtstorey]

Do you have any current dtc”s?

 

[mike_sno]