Narrow band o2 sensors and trimming fuel

[the_buster]

Hi all

I am having trouble getting my narrow bands into the .498 mark and am experiencing difficulty trimming the fuel down. When accelerating I loose my sensor's completely ie voltage drops to 0 and that's without accel enrichment kicking in. with accel enrichment the voltage reads of the scale and then evens out to near .579. VEAL is no longer working and is changing no values in my fuel VE table in either condition. I did read somewhere that an old narrow band could operate "correctly" on a different voltage at ideal AFR's due to it just being old and "coked up". Can anyone confirm that? and why is VEAL no longer working? at idle it sits wobbly on .496 and .579.

Thanks,

[LT401Vette]

[the_buster]

Hi

I have attached my .msq, I did try and capture a log but there is something wrong as no data was in the log! and megalogviewer couldn't play it back. Going backwards very quickly any help would be very appreciated.

Thanks,

EF_XR8.msq

[LT401Vette]

A narrowband is not intended to sit at any one voltage, especially when near stoich. It should oscillate around stoich until you go into open loop.

I can see your VE Table is quite erratic, so I'm sure you have a lot of lean and rich spots. The table really needs to be cleaned up to get your rough tune in order. Those cells that jump from 35 to 81 are certainly going to cause a lot of AFR swings and stumbling.

I really need a data log to see much of how it is actually running though. But for sure you need to smooth out the VE table though.

[vw_chuck]

The 80's called they want their narrowband back. Why would anyone try tuning with a narrowband ?

[the_buster]

The 80's called they want their narrowband back. Why would anyone try tuning with a narrowband ?

Cost. And I'm trying to get a rough tune before I put it on the dyno. Less hassle on the day.

[the_buster]

A narrowband is not intended to sit at any one voltage, especially when near stoich. It should oscillate around stoich until you go into open loop.

I can see your VE Table is quite erratic, so I'm sure you have a lot of lean and rich spots. The table really needs to be cleaned up to get your rough tune in order. Those cells that jump from 35 to 81 are certainly going to cause a lot of AFR swings and stumbling.

I really need a data log to see much of how it is actually running though. But for sure you need to smooth out the VE table though.

I have smoothed out most of those big spots however I still can't get a usable log. I will keep trying but something is definitely wrong.

Cheers.

GOT IT

888.msl

This is at idle.

here is my log when the car was moving you will need to rename the file extension to .rar and decompress it as it was too big to upload.

778.msl

thanks,