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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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O2 Sensors backwards

  • Thread starter Thread starter phutch11
  • Start date Start date May 27, 2007
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phutch11

Member
Nov 14, 2005
328
2
18
May 27, 2007
#1
  • May 27, 2007
  • #1
Hey 5.0 guys,

Can anyone help me out with this issue, the classic guys didn't have much to say...

I've recently completed a 5.0 EFI swap from a 93 into my 66. I went the hard route and adapted the 93 harness to fit into my car. The good news is that the car starts just fine but after about a minute of running well, the idle starts to stumble and then race to catch itself.

I've heard that this may be caused by having the harnesses for the O2 sensors going to the incorrect bank of cylinders. Upon consulting my Hayne's wiring diagram, the diagram only speaks of the sensors as being "Right" or "Left" which is open for debate based on which way you are viewing the engine.

So here's my question: currently my passenger side O2 sensor has the Red/Blk, Gry/Yel, and Blk/Wht wires going to it, with the Gry/Lt Blu, Blk/Wht, and Gry/Yel going to the driver's side sensor. Can anyone confirm if this is correct?

Misc Info - Heads ported, E-cam, No TAB/TAD, No EGR
Codes pulling - 31, 81, 82, 84, 85, 94, 44

Thanks
 

91 HATCH

Banned
May 17, 2007
262
0
0
illinois
May 27, 2007
#2
  • May 27, 2007
  • #2
you could try switching it but i think it would be running rich or lean to where you would be able to tell if it was switched i will go look to see my wire colors
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 27, 2007
#3
  • May 27, 2007
  • #3
This might help

Good luck.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
May 27, 2007
#4
  • May 27, 2007
  • #4
RH side = Bank 1 = passenger side = side with cylinder #1.

It looks like you have the O2's wired right...

I don't remember what all the codes are?
But JRichker will...


jason
 

AnthonyR23

Member
Sep 8, 2006
661
0
16
Ontario
May 27, 2007
#5
  • May 27, 2007
  • #5
if you have the 93 wiring harness... u probably have the same diagnostic as the 93.. if you used the same comp.. which I'm sure you did... maybe check jricher's idle surging checklist... which has a link to checking the diagnostic codes.. (can be found on this site) has the info to do the engine off engine on diagnostics... if your getting error codes.. may point you in the right direction.. just an idea!!
 
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