Nistune Forums

Does anyone know if the standard sr20 auto ecu goes into closed loop mode at idle?

The reason I ask is because at idle it sits steady at about 13.8:1, when i'm cruising around it sits bang on 14.7 so I know the 02 sensor is working properly...
I don't have a consult cable (yet)

Not sure, but i know my car does wierd stuff at idle.

Yes, it will go into closed loop in idle & cruise. Where is the O2 wideband reading from? If using a tailpipe sniffer, these are usually off when at idle, but when there is a greater exhaust flow (ie when cruising) they work fine.

Mine does the same, when I screw the wideband into the bung in my de-cat I get 14.7 @ idle and cruise, but if using the tailpipe sniffer it's normally about 15.5 at idle, but once cruising it's back to 14.7 AFR.

Just not enough exhaust gas flow at idle causing the obscure readings with the tailpipe sniffer.

my wideband is a permanent install lc1, it sits about 1m downstream from the turbo.
I've ordered a nistune chip, so once that is installed i should be able to see exactly whats going on.

Strange, if it's screwed into a bung in the downpipe you should get the same readings on idle as you get on cruise, because it's totally sealed up.

sr20det does open loop in idle! Just like a ca18.

see manual EC20: Open loop control

you are right, i found it in the nissan workshop manual that it is open loop at idle.