Pro Mouse

iTrader: (15)

My tuner has my 408 tuned in open loop.My question is will fouled up o2 sensors hurt preformance?I am wondering if I need new ones?

Frost

iTrader: (45)

Open loop doesn't reference O2s at all

Pro Mouse

iTrader: (15)

So if my car is in open loop it doesnt matter if my o2's are crap or not then?This explains why my LTFT are always at Zero,right?Thanks

Frost

iTrader: (45)

Haha... yeah it explains that

RedHardSupra

iTrader: (1)

yup, just yesterday i 'fixed' a STS car with a completely wacked out fuel trims (+50 STFT on one bank, 60%+ bank-to-bank difference between pulse width, etc) just by disabling closed loop. runs much smoother now, just dont forget to reset the fuel trims once you do that.

racecar

I have been running rich lately trying to get my SD tune dialed in . Last week I saw one LTFT at -4 and the other at +25. One of the 02's was at 125 the other at 800.
Pick up the phone and call the Chev dealer to see if they have some 02's in stock.
Installed them, problem solved.

ringram

You really need to run open loop to tune SD unless you are trying to do it on the NBO2's... which as you now know is a bad idea