Hello and thank you for welcoming me to the forum!
So here it goes,
i have an 86 crx si getting 16mpg city. idling at 17-2100 rpm before engine light kicks on, 13-17 after it kicks on. intermittent light, on off every 15ish minutes.
my ecu is throwing code xxxo (faulty o2 sensor)
i replaced the o2 sensor with an exact fit (40 bucks!!) and no problems were fixed.
i know i have no vacuum leaks... i am at a loss here. any ideas? what should i check? ps, at extreme cold ambient/coolant temps car runs extremely rough/misfires on throttle + always smells rich.

also, when i got the car the brakes ceased up on the way home, got new rotors calipers pads, problem persisted got new brake master cyl. problem apeared to be fixed but now I am showing signs of brake master cyl issue, press on brake feels very squishy and fades all the way to the floor, yet car "wiggles" at stop completion as if the front right wheel is doing all the work, could this be a proportioning valve problem? or brake booster? or did i buy a faulty master cyl? any help is much appreciated... thanks!!

I will def. be around the forum now, will probably make a build/resto thread, thanks!
-Josh

 

wow thanks for all the help guys! i have learned a lot here.
but seriously, honda owners have got to be the biggest.....
nevermind.
sold it and got a nissan.
they help people out on their forums.

 

Fast idle valve allowing too much air.

 

bingo!!!

 

o2 sensor wires couldve been ripped etc
and what hondaguy said. clean out iacv.
get a vacuum gauge and see where its reading. should be at least 20hg