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1995 Gt Runs Like Crap - Code Help Please

  • Thread starter Thread starter 5.0L Miata
  • Start date Start date Jul 7, 2014

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Jul 7, 2014
#1
  • 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?

Brett
 

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Jul 9, 2014
#2
  • Jul 9, 2014
  • #2
No thoughts? I purchased a new O2 sensor last night and will try replacing the passenger side and see what I get.
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
424
154
Boca Raton, Florida
Jul 9, 2014
#3
  • Jul 9, 2014
  • #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.
 

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Jul 9, 2014
#4
  • Jul 9, 2014
  • #4
Ok will do. Thanks.
 
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