o2 or not to o2

[Navigator]

A good tutorial on the O2 sensor popped up a few weeks ago. I will be eliminating the 02 sensor when I install my PC3. I believe that is the most common configuration.

It may not be that way with the EPA friendly Street Approved PC3 though.

 

[atomsplitter]

The biggest reason to have the O2 sensor is to run the ECM in "closed-loop" configuration. That allows the fuel maps to be leaned out to maximum when running steady state throttle conditions. Eliminating the O2 sensor input keeps the fuel mix richer steady state so throttle response is faster (doesn't have to ramp up fuel). Most of the folks doing the PC3 or Tuneboy have little interest in going "green" they do it for more grunt. You can decide which way you want to go, my guess is you'll not be putting the O2 sensor back into the loop.

 

[Navigator]

The biggest reason to have the O2 sensor is to run the ECM in "closed-loop" configuration. That allows the fuel maps to be leaned out to maximum when running steady state throttle conditions. Eliminating the O2 sensor input keeps the fuel mix richer steady state so throttle response is faster (doesn't have to ramp up fuel). Most of the folks doing the PC3 or Tuneboy have little interest in going "green" they do it for more grunt. You can decide which way you want to go, my guess is you'll not be putting the O2 sensor back into the loop.

Hmmm. I might try leaving it at first. The present performance with the Jards and with no PC3 is entirely satisfactory and fuel economy has not suffered. I'd like to maintain that balance while eliminating the back popping.

 

[atomsplitter]

The biggest reason to have the O2 sensor is to run the ECM in "closed-loop" configuration. That allows the fuel maps to be leaned out to maximum when running steady state throttle conditions. Eliminating the O2 sensor input keeps the fuel mix richer steady state so throttle response is faster (doesn't have to ramp up fuel). Most of the folks doing the PC3 or Tuneboy have little interest in going "green" they do it for more grunt. You can decide which way you want to go, my guess is you'll not be putting the O2 sensor back into the loop.

Hmmm. I might try leaving it at first. The present performance with the Jards and with no PC3 is entirely satisfactory and fuel economy has not suffered. I'd like to maintain that balance while eliminating the back popping.

Best solution for decel pop is to richen up the bottom end fuel tables by 10 to 15%. You should print your current map (starting point) then raise the numbers 10% (the .net site has an example). If the decel pop is still there add another 5%. The decel pop is reduced dramatically or eliminated altogether.

The pop is due to the off-throttle fuel mix being too lean. Fatten than part of the table up and it should disappear. Good luck.

 

[Navigator]

I'll have to take a close look at the map I selected selected from the ones provided on the PC web site. N1 used the same one and had no backpopping. However, he was running in an open loop with the 02 eliminator installed.

I am not sure how to customize those maps but I'll do some research or otherwise figure it out. Thanks for the tip there Atom.