i went and got a tune recently... my left bank o2 at idle was .9 something while the right was .8 something.. my tuner said i have a lazy o2.. does that sound right?? say if the o2 is fine and one bank is just a little richer.. can one bank be leaned out? it could be a issue of cam degs off from one bank to another right?
left bank vs right bank
- Thread starter cobra916
- Start date
You'd have to look at the datalogs. 99% of the time the banks will be off from each other. Just the nature of the beast. If one bank is reading extremely lean and one is extemely rich then I'd worry. But given how close your's are, I wouldn't worry about it.
The fuel trims never stay still. They're always bouncing up and down. It's the computer trying to correct the A/F. Ideally you would look up your STFT and it would read 1. But that'll never happen. So tuners shoot for a 10% swing. Meaning the fuel trim will change from .95 to 1.05. And that's considered normal.
How many miles are on your current sensors? Are you running long tube headers?
The fuel trims never stay still. They're always bouncing up and down. It's the computer trying to correct the A/F. Ideally you would look up your STFT and it would read 1. But that'll never happen. So tuners shoot for a 10% swing. Meaning the fuel trim will change from .95 to 1.05. And that's considered normal.
How many miles are on your current sensors? Are you running long tube headers?
my car has 39k on it.. and yes i have long tubes with no cats
Did he increase the duty cycle? That might help with the slow response.
not sure but even if he did.. both would react slow? one bank is always laggin behind the other..never are they the same.. atleast at idle what he showed me..
am i totally wrong ?
One side of mine always seemed slow. And when I threw the response code it was always on one side. Once I increased the transport delay and duty cycle the code went away.
i am very wet behind the ears..so can you break this down for me.. so you would increase transport delay and duty cycle only on that one side to make the both sides equal.. are you tricking the ecu or are you leaning out that one side?
can you explain the bold words more? thanks
The transport delay is basically the time it takes the O2 sensor to heat up. The computer expects the sensors to be fully heated up in a certain amount of time. The duty cycle is the internal heating circuit. The sensor uses the heating circuit as well as exhaust to heat up. By moving the sensor further down stream by installing long tubes it's going to take longer to heat up because the exhaust is cooler by the time it gets to the sensor. Because of that longer time the computer is going to think the sensor is slow and going bad. By extending the transport delay in the tune the computer gives the sensor more time to heat up before thinking it's bad. And increasing the duty cycle of the heater allows the sensor to come up to temp by using more of the internal heating circuit.
The changes you make affect both sides. There isn't an independent table for each bank.
The changes you make affect both sides. There isn't an independent table for each bank.
:beer: your the man !! i dont care what anyone says!!
Thank you. Just glad I could help.
Users who are viewing this thread
