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Code 172 and 173??

  • Thread starter Thread starter 94' Five.0
  • Start date Start date Nov 4, 2007

94' Five.0

Founding Member
Jun 11, 2002
206
0
16
Raleigh, NC
Nov 4, 2007
#1
  • Nov 4, 2007
  • #1
My equus reader came in over the weekend and I finally got around to pulling codes. The CEL has been coming on randomly but I haven't noticed any major difference in how the car is running. Here's what I got...

172 - Heated oxygen sensor indicates lean condition, right side
173 - Heated oxygen sensor indicates rich condition, right side

My first guess is just a bad sensor since it's showing both lean and rich? Anything else I should check out before simply assuming it's the sensor?

Thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Nov 5, 2007
#2
  • Nov 5, 2007
  • #2
There are issues with the MAF signal that can create a rich issue at idle and lean issue at WOT but since it's only spitting the code for one side..............

I would swap the sensors (left to right, right to left), reset the KAM and drive it. If the code goes to the left side, it's a good bet the sensor is bad. If not, you just possibly saved some money...............
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 5, 2007
#3
  • Nov 5, 2007
  • #3
What JT said

He is always right on the money with helpful info

Grady
 

Zero_chance

Founding Member
May 29, 2001
1,244
7
59
Maricopa, AZ
Nov 5, 2007
#4
  • Nov 5, 2007
  • #4
Just make sure to take your time and use the right tools so you dont strip them out in the process.
 
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