Closed loop / open loop

[87-WE2]

When the car is warmed to optimum temp, should it be in open or closed loop?

Mine is hot now and is apparently in open loop at idle because o2s are steady at idle and cc's don't move. While actually driving, the o2's move around and cc's increase.

 

[87-WE2]

Well it just made a monkey out of me. Now the cc's are jumping at idle, but o2's are relatively steady!
I made a video but can't post from the phone app.

How do you know whether you're in open or closed loop?

 

[earlbrown]

You might have a tired O2. The cc's are telling you how many times the O2 commanded the ECM to move fueling above and below 14.7:1. Yours sounds like it might get lazy at idle when it cools off and wakes up when you put a little bit of heat to it.

 

[87-WE2]

Thanks for the quick response. Does the sm let me know if I'm in closed or open somehow? Seems I remember that It does, I just don't remember how to tell.

 

[87-WE2]

I think you're right earl. Now I'm getting some effed up readings at wot also. Like 246 at 90mph!! Im convinced its bs because i Verified fuel psi is keeping up with boost psi. At 24psi it's around 66-68 psi.

I gotta get this PL hooked up!!

Thanks for the help earl. I'm glad youre back visiting regularly cause youre always willing to help us noobs.

I'll pick up an o2 and replace it some day. Busy weekend ahead.

 

[trixdout]

I've been having the same issue with my o2. No knock at all, pl hooked up, sm 2.2 chip in, and the o2 sensor behaving rather strange. At times it will be in closed loop while driving then closed while idling and then vice-versa. Plus it will be closed at idle, open at driving and that switches. This occurs in all rpm ranges.

Need my wideband installed immediately.

Sent from my iPhone using Turbo Buick

 

[87-WE2]

What tells you that you're in closed or open?

 

[earlbrown]

If the decimal point in the retard display is blinking, you're in open loop. When it's solid, that's closed loop. (or you could install the powerlogger and it'll tell you when you're in closed loop ) That's per the instructions. I've never payed attention to see if it works like that after installing the powerlogger scanmaster chip.

some chips like the turbotweak run open loop at idle but I don't know if it reports it to the scanmaster either.

http://www.fullthrottletech.com/attachment.php?attachmentid=172&d=1135610103

 

[we4Mateo]

If the decimal point in the retard display is blinking, you're in open loop. When it's solid, that's closed loop. (or you could install the powerlogger and it'll tell you when you're in closed loop ) That's per the instructions. I've never payed attention to see if it works like that after installing the powerlogger scanmaster chip.

some chips like the turbotweak run open loop at idle but I don't know if it reports it to the scanmaster either.

http://www.fullthrottletech.com/attachment.php?attachmentid=172&d=1135610103

You're right on. The TT chip will flash the decimal at idle when in open loop, on a non-powerlogger setup at least. Bailey chip can run open or closed at idle so you need to check how it's setup for you, but scanmaster decimal always works for me. It'll flash again, open loop, while in lean cruise mode so know if your chip has that enabled b/c it may go open loop, flashing decimal, even at cruise with lean cruise on.