ECU reflash by ECUnleashed review..

[Andy Hollis]

Here's an example of what I was talking about. This is an Injen versus stock airbox, done five minutes apart. Car has Dynotronics' tune on it and stock exhaust manifold, second cat replaced by Burns straight-through and a dump. I am driving here, and I'm pretty consistent on a dyno but even still did not get the starting rpms identical.

Notice how the Injen plot (the higher one) is actually a touch lower than the Stock airbox up until 4200 rpm. It goes higher just as the AFR goes down to 13.1.

To my knowledge, no one has yet figured out how to force the thing into open loop at WOT always. You can tell if you have a real-time OBDII data logger running (Joe lent me his while we were working on my tune). I did find that when the a/c is on, it forces open loop. There *might* be a way to have the a/c think it is on, but not have the power-robbing compressor actually engaged. Something to think about.

For now, just be super-consistent in your dyno comparisons.

 

[CorkSport]

I can give the A/C switch a try, our shop car has the A/C delete pulley for B-Spec. Let me see when I can arrange it with the engineers.

-Derrick

 

[Andy Hollis]

I can give the A/C switch a try, our shop car has the A/C delete pulley for B-Spec. Let me see when I can arrange it with the engineers.

-Derrick

Sounds good. I assume you have a real-time OBDII datalogger at your disposal. With that, you should be able to tell for sure. There's an OBDII variable for closed loop/open loop operation, and you can also tell by watching the primary O2 sensor readout.

I played around with tons of stuff and it appears to be some combination of WOT, temp, and rev history that makes it go open loop. In an autocross setting, once I got it open, it stayed that way for the rest of the run. Same on the track. But just driving around and punching it every once in awhile doesn't work. Which makes consistent dyno comparisons more of a challenge.

 

[zps2004]

Yea I figured it was switching from closed loop to open at that point, but I didn't know that the transition was still something that they were working on with the tune for the 2. Makes sense now. I wonder how fast then it goes back into closed loop. Maybe it would be best to hold the car at WOT for a bit before starting the run so it is in open loop the hole time. That could lead to some temperature consistency issues, but maybe not.

 

[CorkSport]

Sounds good. I assume you have a real-time OBDII datalogger at your disposal. With that, you should be able to tell for sure. There's an OBDII variable for closed loop/open loop operation, and you can also tell by watching the primary O2 sensor readout.

I played around with tons of stuff and it appears to be some combination of WOT, temp, and rev history that makes it go open loop. In an autocross setting, once I got it open, it stayed that way for the rest of the run. Same on the track. But just driving around and punching it every once in awhile doesn't work. Which makes consistent dyno comparisons more of a challenge.

We have one of the new dyno dynamics units which has the interface for the OBDII. I will make sure we can log it before we give it a shot.

-Derrick

 

[cosh68]

Might be "preaching to the converted" but I was monitoring Mode 1 PID 03 on the way home from work...

A0 Open loop due to insufficient engine temperature
A1 Closed loop, using oxygen sensor feedback to determine fuel mix
A2 Open loop due to engine load OR fuel cut due to deceleration
A3 Open loop due to system failure
A4 Closed loop, using at least one oxygen sensor but there is a fault in the feedback system
A5-A7 Always zero

Everyday accell & decell kept it in closed loop A1, could kick it into A2 with a foot full of gas & throttling off hard pushed it into A2..... as speed rose after a bit of gas that kicked it into A2 it would ease back to A1 as the speed increased & load dropped...

Shaun.....