- Wed Jun 08, 2022 7:09 pm
#154028
Dual wideband sensors, one on each side of an xpipe. Innovate system gauge on driver's side and VEMS ECU on passenger side. The Innovate is a 4.9 sensor and VEMS uses a 4.2 sensor FWIW.
Tuning ECU on the passenger side, things seemingly going well, but noticed AFR's on the driver's bank were running two whole points higher. 14's on Vems side was getting 16's on innovate gauge.
I will have to get more data but my memory is that the numbers would get closer together at high loads/WOT, but consistently off at idle and cruise.
Today I switched the sensors. Put the innovate sensor on the passenger side and VEMS sensor on the drivers side.
Unfortunately, the number's reproduced: driver side (now vems) showing 16's at warm idle and passenger side (now innovate) showing high 13's.
Because two independent sensors are giving me the same lean reading I am assuming it's real, and now engine related.
Which sucks, but what are my rule outs here?
Injector malfunction?
Vacc leak? unlikely, just did extensive smoke and boost leak testing on the top end which it passed.
Exhaust leak up stream from O2 sensor?
Compression/leak down issues on that side? Recent compression test was 'ok' on that side, the only lower numbers (155) were on the other bank. No leak down testing done yet.
Ignition or grounding on that side?
What else?
Thanks ahead of time.
Tuning ECU on the passenger side, things seemingly going well, but noticed AFR's on the driver's bank were running two whole points higher. 14's on Vems side was getting 16's on innovate gauge.
I will have to get more data but my memory is that the numbers would get closer together at high loads/WOT, but consistently off at idle and cruise.
Today I switched the sensors. Put the innovate sensor on the passenger side and VEMS sensor on the drivers side.
Unfortunately, the number's reproduced: driver side (now vems) showing 16's at warm idle and passenger side (now innovate) showing high 13's.
Because two independent sensors are giving me the same lean reading I am assuming it's real, and now engine related.
Which sucks, but what are my rule outs here?
Injector malfunction?
Vacc leak? unlikely, just did extensive smoke and boost leak testing on the top end which it passed.
Exhaust leak up stream from O2 sensor?
Compression/leak down issues on that side? Recent compression test was 'ok' on that side, the only lower numbers (155) were on the other bank. No leak down testing done yet.
Ignition or grounding on that side?
What else?
Thanks ahead of time.
Devolved 86.5 Track car
Manual w/LS
DIY Supercharger
Manual w/LS
DIY Supercharger