1995 Gt Runs Like Crap - Code Help Please

Discussion in '1994 - 1995 Specific Tech' started by 5.0L Miata, Jul 7, 2014.

  1. Hello Everyone,

    I have just installed a new engine in my 95 GT (stock short block, eddy heads, b-cam, 24lb injectors, Cobra intake, 70mm TB, 90mm MAF, shorty headers, flowmaster exhaust, x-pipe, etc.

    The car starts and idle fine now but is running like crap. No power through the gears, feels like its missing, and I've only driven it 5 miles but I have a check engine light on. Ran codes and I get:

    511, 173, 176, and 543.

    511 I understand is because I have a chip installed for the mods mentioned above. The others I know are 02 sensor and fuel pump related but I don't have any more details. Any thoughts on next steps?

  2. No thoughts? I purchased a new O2 sensor last night and will try replacing the passenger side and see what I get.
  3. 173, 176 are lean / rich codes to the O2 sensors. Replace them and it should go away. I use to clean mine every once in awhile but that's just a bandaid. Also if the O2 wires have been extended / cut / repaired it will also throw these codes. The 543 is related. Do the O2's and clear codes.
  4. Ok will do. Thanks.