Stock FI LED question

[eec564]

If I look carefully while driving at night, I can see my little O2 sensor LED blinking on and off while I'm cruising. My question, if anyone happens to know off hand, is the engine running slightly on the rich side or lean side when the LED is lit? I ask because once I get a bit above 80, the LED stays lit solid, but if I floor it the light goes back off. I'm just curious if I'm running lean (and possibally getting slightly better milage?) when I'm moving at a decent speed and not flooring it and thus kicking in the acceleration enrichment.

 

-Eric

 

[mario_82_ZXT]

Each time it flashes it is reading the O2 sensor I think.

 

It stays on become it goes into open-loop at a certain rpm and ignores it (just uses a preconfigured fuel map).

Mario

[eec564]

Yea, normally I'd agree with you. The thing that makes me think the LED says something is it has roughly a 50% duty cycle. Also, the light goes off once I hit the point where my WOT contact in the TPS and the car takes off like a bullet as it ritchens up instantly.

 

I see no reason why it couldn't be going into open-loop mode at 3600rpm (about 75mph in 5th gear) with the light on solid then uses open-loop mode with the light off in WOT mode. That just seems a bit odd to me, as isn't the closed-loop system controlling the LED, and that system would be ignored completely in open-loop, or dissabled completely puting the LED in a certain state all the time the system isn't being used?

 

I may break down and take appart my ECU and trace the circuits if I get ambitious and nobody knows. I guess I could always use some old DAC hardware I have laying around and make a plot of LED on/off and narrow-band O2 voltage. Might be easier.

 

-Eric