alright... I got code 1 on my ecu. I know its generally the o2 sensor. And I fixed it... but when I drive at highway speeds despite replacing the o2 sensor I still get a code 1 on the ecu... so my question is... What gives?!? What should I do next? any advice because I want my baby to work again man... its driving me nuts... HELP!!!

 

Read through this and do the troubleshooting to make sure the wire isn't busted or somehow got a bum o2 sensor.

 

O2 sensors are for reading the exhaust gases and making slight corrections. If your engine is outside of the parameters the ECU can adjust for, you will get a code. A code 1 is more often a working O2 sensor reading a rich or lean exhaust than it is a bad sensor.
Check your ignition timing and your cam timing.
It would also help if you listed what engine you have and any modifications you have done.

 

Well I have an 89 honda civic dx with a d16a6 swap. No major mods beyond that. dx tranny and a k and n drop in air filter.

 

check continuity between o2 plug and the ecu

 

Was the swap recent, did this start after the swap. Did you do a DPFI-MPFI swap, if so it could be a wiring issue. I'm still thinking timing though.

 

well... it was a full swap from d15 to d16a6 but yeah I am starting to think timing as well...