Hi,

I've installed a prosport wideband in my 2RZ naturally aspirated. What should I expect to see on the AFR when idling and driving around?

I'm getting very poor fuel consumption, about half of what previous owners got. I suspected over fueling. I checked IAT, water temp, timing TPS, fuel pressure etc. I have no means to check MAP yet. Injectors are not leaking. I took my manifold off to install the O2 when I discovered it had a hairline crack between 2 and 3. Replaced it with a set of branches. Installed O2 between branches and stock exhaust.

My setup does NOT have a factory O2. The ECU has no idea what is happening at the exhaust, hence my O2 installation to check things out.

Given the ECU has no means to check exhaust AFR the cracked manifold could not have contributed towards bad consumption by making the O2 read lean. Currently the idling AFR is about 15.3, driving around about 12.5

I therefore can't acount why I'm getting bad consumption if the AFR seems normal from what I've read on the web. I have not checked valve timing or clearance but again the AFR should show differently if things were not good, right? Where is this extra fuel going?