i have a air/fuel ratio guage, lately it's ALWAYS pegged on the last green saying MEGA RICH condition. ONce in a blue moon it will sweep the guage like normal, but it's not a common occurance. And yes, the guage did work fine when i first got it, started acting kinda funny like 4 months ago i suppose, and getting worse.

Anyway, after driving the car for about 45 min, i read out this data from the pcm at idle

fuel trim C 16
long term Fuel trim B2:-3% 124
" " " " B1:-9% 118
short term fuel trim B2: -3% 126
" " " " B1:-3% 126


I'm not sure what this all means, but i recorded this data because i thin kit's the long term BLM's?? ANyway, i also tried to read the o2's themselves, they all seem to fluctuate so fast i can't tell where they are ranging that well, it looked like they where going from 50mv to about 300mv??? i oculd be wrong on that though. ANyway, can someone shed some light on my situation?? Running rich or broken/cheap guage. Thanks.

 

Those air/fuel ratio meters are garbage UNLESS it's a wideband setup. It can only accurately identify rich or lean in relation to 14.7:1, which in many cases(WOT for example) is a useless figure.

Under normal driving, your car's O2 sensors should be jumping back and forth between values under 450mv and over 450mv. With your car at WOT, look for values right around 875-900 mv...although only a wideband setup will give you exact values.

If you still suspect an issue, my first question would be how old are the O2 sensors? Any damage to the sensor harness? Any exhaust leaks?

 

both O2s think you are running rich so your PCM has leans out one bank by 3% and the other by9% and apparently you are still running rich, I would guess the o2s are right and you have a misfire or an exhaust leak.

 

ok, i'm going to check if it's in closed loop next, Also, which side is bank 1??? is that the driver side, thats where my AF guage is hooked up too. I guess i'll get some more data, and check for exhaust leaks, i doubt i have a misfire the car runs like a champ.
Thanks again

 

Like was stated before ...those non-wideband meters arent very useful. Your LT block learns are within 10% so I woundnt be too concerned at this point but keep an eye on it.

 

yeah, thats true, it could be that your mods have increased airflow by 3% which is why your car has to add 3% more fuel to compensate. I wouldn't worry too much about it.

 

According to this data, at idle your car is correcting for a rich condition and subracting fuel (-3% and -9%). That means if your car wasn't subtracing fuel, it would be running rich. You really should drive around and get some more long term fuel trim data for several other cells besides idle. I wouldn't worry about your long term fuel trim cell 16, that's pretty much what mine looks like.

 

Bank 1 is driver's side.

 

UPDATE: installed a scanmaster, says 950mv at WOT. ALso, looked under car, i can see that the PASSANGER side collector has a blown gasket, 1/3 of the gasket is burned thru. I'm going to go to an exhasut shop to see if they can seal this collector better then me, i've been battlingg gasket problems on this collector for a year. I have as&m headers mounted to a random tech pipe. I tried felpros, doubled up felpros, felpro's with RTV, and percy's aluminum gaskets. THe aluminum lasted the longest(6 months) b4 it blew. I hope the exhaust shop can do something that I'm not aware of.

THis being said as fact, would this explain any of the data?? THanks again