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Trouble codes

  • Thread starter Thread starter loud 95
  • Start date Start date Dec 31, 2004

loud 95

New Member
May 29, 2003
562
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0
Milwaukie, OR
Dec 31, 2004
#1
  • Dec 31, 2004
  • #1
Since installing my chip, my car has begun to throw the following codes:
172: Lack of heated oxygen sensor switches indicates lean bank 1.
176: Lack of heated oxygen sensor switches indicates lean bank 2.
543: Fuel pump secondary circuit failure battery to control module.
What do I do to fix the problem regarding this last code? What exactly is the problem? Any help would be appreciated.
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
424
154
Boca Raton, Florida
Dec 31, 2004
#2
  • Dec 31, 2004
  • #2
It's running lean which means you need to bump your fuel pressure up a few pounds. If you don't have an adjustable fuel regulator those codes are telling you to get one. Don't worry about the 543 unless the car doesn't want to start. Did you mess with the injectors or fuel pump? Could have run the fuel tank too low.
 

loud 95

New Member
May 29, 2003
562
0
0
Milwaukie, OR
Dec 31, 2004
#3
  • Dec 31, 2004
  • #3
I have an adjustable reg, so I will turn it up. Currently, it is 40psi at the rail. I have a 255lph in tank pump, which has had no problems thus far.
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
424
154
Boca Raton, Florida
Dec 31, 2004
#4
  • Dec 31, 2004
  • #4
Don't forget to reset the codes so your starting from scratch again. I get the 543 when I work on the fuel system. Swapped my injectors 3 times and got it. Also got it when my tank was empty on an incline. Got it when I changed my fuel pump.
 
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