BOA279

iTrader: (1)

I put an AFR (Air fuel ratio) gauge on my 98 LS1 camaro over a year ago. I noticed that it goes full lean then full rich about once a second causing an audible "click" every time it maxes out the gauge in either direction. At first I thought it was due to the restrictions I put in my exhaust to pass inspection over here in Germany and I lived with it for about 6 months. Before I put it away for the winter however I put on a new Magnaflow cat back on and it was exactly the same. The previous exhaust was an SLP loud mouth which read 124dB and to pass I had to weld the right side shut. It dropped to 118db I believe so I packed the left side with about a foot and a half of steel wool to pass and removed the steel wool the same day. I figured the back pressure was causing the reading but to this day it still slaps full lean full right over and over the entire time. The only time it tries to stay steady is near or at WOT. What gives?

ShortChevy

iTrader: (21)

Sounds like you have a narrow band AFR gauge which is about useless

Q8-TECH

as mensioned make sure you have a wide band sensor and not a narrow band. If you do know for sure that you do have a wide band sensor and the proper controller to go with it, then i would start by checking your ground.

BOA279

iTrader: (1)

are the stock o2 sensors wideband? If so then that's definitely the problem as the gauge is narrow band. I assumed it was narrow.

outkast6991

iTrader: (34)

stock 02's are narrow band.

BOA279

iTrader: (1)

ok so the o2's and gauges are narrow band...looks like I need to investigate my wiring then or does anyone else have a suggestion?

batboy

iTrader: (6)

Yes, stock O2 sensors are narrow band. I don't see how an AFR gauge will give you true readings with a narrow band sensor. You need a wide band module and wide band sensor. That said, I had a wide band sensor go bad once and at WOT it would peg full lean. It worked fine again after I replaced the sensor.

BOA279

iTrader: (1)

I assume its just a multimeter that reads .1 to .9 volts and displays that on the gauge as lean to rich. I'm thinking that I need to ground the gauge to the block or battery instead of the frame as the voltage is so minimal I may be loosing some of the signal to a bad ground.

MeentSS02

iTrader: (11)

Narrow band O2 sensors constantly switch back and forth...that's why they can't be used or trusted for anything other than stoichiometric operation, hence why the engine switches to open loop at WOT.

If they are swinging back and forth constantly, they are operating normally.