HELP NEEDED. CODE 231 ON A2 SOCKET

[RUIAMARO]

HAVE A PROBLEM WITH MY 855 T5 (1994). I START THE ENGINE AND I'VE GOT GREAT DIFFICULTIES WITH ACCELERATING IT (THE IDLE IS INCONSTANT). I HAVE READ THE CODES 231, AND SOMETIMES, 143 AND 212 (ON A2 SOCKET).
WHEN I CLEAR THE CODES, EVERITHING COMES BACK TO NORMAL, BUT IF I RUN THE CAR FOR SOME TIME IT COMES BACK AGAIN. THE LAMBDA LIGHT ONLY LIGHTS UP WITH 143 AND 212.

APRECIATE IF ANY OF YOU COULD HELP ME.

[Pete]

231 - long term fuel mixture too weak or too rich in part load stage
143 - front knock sensor signal absent or faulty
212 - heated oxygen sensor signal absent or faulty
it looks like your problem may lie in a few components, try swapping the knock sensors over to see if its the front one really at fault or if its a wiring problem, secondly there seems to be a problem with the oxygen sensor, check its wiring or other wise you may have to replace it, oxygen sensors are fairly interesting items some will last for ever but others will clap out really quick it really depends how the cars being run. ive found disconnecting the battery for a hour or so then reconnecting it allows the ecu to loose its memory then as your driving relearn your driving style. give it a few shots it may just be the parameters for the components have changed a bit and the computers being so sensitive as they are have picked up a problem and is alerting you to it. good luck
pete

[dpauto.com]

Sounds to me you have two problems.

DTC 143 is a hard code. You definitely need to change your knock sensors. There are new upgraded knock sensors that are now available.


Repeated DTC 212 is most often indicating your O2 sensor is not working and can cause poor idle and lack of acceleration performance.

[matthew1]

My 212 caused poor fuel economy. Replacing the sensor took care of the light and the economy. Easy 30-minute job, unless you can't get the wiring harness reconnected like me, in which case the job becomes 75 minutes long.