Hondata

I changed the analog to d10 and it’s better but I still get an erratic lambda voltage. Jumps .2-.5 volts.

I’m thinking it’s a grounding issue. It’s a aem uego wideband. Should the gauge main ground be to battery or thermostat and the analog ground to the analog ground in the hondata or on thermostat?

Changed the alternator. Same issue. Car will be idling and the lambda voltage will be steady at idle. Then randomly it’ll start going erratic. Can’t even read a steady voltage. Gauge is steady. I’m gonna take a look at my ground and wiring.

Can a failing alternator cause the lambda voltage to behave erratically? Cars tuned professionally. Been driving it for a year now. Noticed the lambda voltage wasn’t steady. Afr on aem gauge is fine. Had my alternator tested. Failed. Gonna replace it, just wanted to see if something else could be ...

D15b2 1990 civic std
Mpfi conversion
Td04 turbo
S300v2
390cc injectors with resistor box
Obd0 to obd1 jumper
Intercooler
Z6 intake manifold
Skunk 2 half rad
Mishimoto slim fan
Aem x series wideband

Anything I should look at in terms of this voltage fluctuations?

Ok on cold start it was reporting 10.1:1 and after 20 seconds it would be at 12.1:1. Afr target for lambda was 13afr at 30 degrees. Ect compensation was at 18 percent. Gonna lower the ect compensation fuel and see if it improves.
Also I have a question regarding battery voltage. My Hondata reports ...

Ok. I wasn’t sure if it was ok to warm up the sensor. I had a mtx-l and it warranted to not let sensor warm up before starting. Switched to a x series

So I’m having this issue when the weather gets below 40 degree f. Car will crank and start but it will idle low. It doesn’t die but after 10 seconds it’ll smooth out and idle at my target. I should mention that if I do give it gas within the first ten seconds and let off the idle will jump back down ...