Closed loop?

[curtisparker82]

HOW DO YOU TELL IF YOUR CAR IS IN CLOSED LOOP? I HAVE 2002 ZX5 ZETEC AUTO THATS GOT A SLIGHT MISS AND ITS GETTING HORRIBLE MPG. I HAVE A GOPOINT CABLE FOR MY IPOD TOUCH AND IM TRYING TO FIGURE THIS OUT. ANY HELP WILL BE GREATLY APPRECIATED..

[Sponsor]

[Elizabeth]

As soon as the car is fully warmed up with the engine still running it will be in closed loop.
Open loop is when it is 'adjusting' itself like from a cold start.

[TerryB]

There's still no way of knowing just because it warms up. I use an Ultragauge and it shows when it goes into a closed loop. I can also see what my fuel trims are. The circle in the upper right of the screen shows a closed loop. At start up, it shows a broken circle. It takes about 20-30 seconds for it to be closed.
http://www.ultra-gauge.com/ultragauge/index.htm

[1turbofocus]

You can use a volt meter on the o2 wiring and see if your voltage goes up and down , it takes anywhere from 30sec to 3 min to go closed loop , car starts in open loop then switches to closed loop

Spend the datalog money on a xcal3 then you get a custom tune , datalogger and checks and clears the CEL or find some on here on FF close to you that has a xcal and do a datalog and I will be glad to look at it for you

Tom

[iminhell]

O2 fluctuating does not indicate it's in Closed Loop.
Normally it will, but there are instances when it won't.


Regardless, the 'miss' probably isn't related to Open/Closed Loop.
Look up the DPFE info. It's the common one and 75% chance it's your problem.