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Cel Help - Here Are The Codes

  • Thread starter Thread starter 5.0L Miata
  • Start date Start date Jun 20, 2015

5.0L Miata

Member
May 3, 2005
121
0
17
Ontario, Canada
Jun 20, 2015
#1
  • Jun 20, 2015
  • #1
Hey Guys,

I need to have an emissions test done on my car but I know it will not pass with the CEL on. The CEL seems to come and go as I drive and I don't notice and driving issues. Here are the codes I get:

511 - No worries I have a chip installed
173 - 02 fault rich
177 - No 02 sensor switch
179 - Fuel system lean
188 - Fuel system lean

Thoughts on the cause? Am I looking at new O2 sensors to fix this?
 

toyman

10 Year Member
Jul 19, 2007
1,944
54
79
Vernon BC
Jun 20, 2015
#2
  • Jun 20, 2015
  • #2
May be as simple as a dirty MAF sensor element. I would clean it first. If the codes still persist after they have been cleared, then switch the O2 sensors to see if the problem follows the sensor. If it does then the O2 sensor is likely the culprit.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
Jun 21, 2015
#3
  • Jun 21, 2015
  • #3
Check for vacuum and exhaust leaks.
 
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