Hondata

1995 Honda Prelude
H23 VTEC Blue Top
T3 T04E 60 trim .63 A/R (@ ~7 psi)
TRE Performance 255 LPH Fuel Pump
TRE Performance 1000cc injectors
AEM 30-4110 AF Wideband
P06 ECU s300 (v 2.7.7.0)

Hi All,

I'm running into major voltage inconsistencies between what is being read with my voltmeter and within sManager. I've been using analog inputs.

Here is the wiring
- AN0 (analog input) for the 0-5v
- GND (analog input) used for grounding
- A25 on ECU used for power

I've probed my voltmeter between AN0/GND connections to the wideband.

Readings on the voltmeter are saying 1.6 to 2.3v, however, Lambda Voltage on sManager won't move past .7 to .8v. It'll also jump to ~5v whenever it feels like it. Then, looking at the individual AN inputs (that aren't connected to anything), all AN inputs are going wacky. they are all fluctuating between .01 and .17v. It's not making any sense to me and severely affecting my ability to tune.

I've tried connecting back to D10 (w/ both resistors removed) while still having CL in narrowband (so I can view the voltage changes) and it's better but still inconsistent. Any guidance on this would be appreciated.

If you are trying to use the wideband in D10, then you need to change it to "closed loop wideband input". You cannot have it set to a narrowband input. You cannot run closed loop from the analog inputs on the s300 itself.

I recommend using a switched power source at the fuse box for power and a solid chassis ground for the ground and see if that has any effect.