b20vtecturbe

i was wondering is a car measured for being to lean at the o2 sensor or is it measured at the exhaust...my car is completly stock its a ej1 with a d16z6 stock the one thing i noticed is that i have a exhaust like at the midpipe toward the header its self....so i was wondering if the o2 sensor measure the lean/rich area of a smog check or if its out the exhaust...trying to fix without paying a repair shop to diagnose problem

worlds-slowest-EG

it's measured at the tailpipe but a leak can cause a lean condition. get the leak fixed then try again

b20vtecturbe

thank you thats what i figured, im suprised the smog guy didnt tell me or mention it to me..i just wasnt thinking about it at first, cause i actually wantd to see if it would pass before i go and start replacing everything for no reason...so ill just fix the leak and try again

jooky5

wouldn't a lean running car be better for emissions?

Koopa Troopa

Don't try to make sense of things that are government run. =P

jooky5

sorry, your totally right. What was I thinking.

Former User

Running lean is bad for the engine and increases NOx emissions.