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Unread 04-28-2012   #1 (permalink)
Red97 is offline Rookie


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Default 92 5.0 code 91??

Hi ive got a 92 with a 331
Driving tonight engine light came on, when i got home i did koeo test, and got codes 15 (i have a chip) and code 91. i cant find my code list and when i searched online i found a bunch of different listings for 91. so can anyone tell me what 91 really means. And any ideas on how to fix
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Unread 04-28-2012   #2 (permalink)
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For an 89 lx 5.0 ho code 91 one is one of the o2s is lean I forget which one. But go to www.fordfuelinjecrion.com they have code lists there
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Unread 04-28-2012   #3 (permalink)
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Well, if I were a woman I'd say put some black tape over it and bam it's fixed! LOL, but I'd give your dealership a call if I were you. Or maybe O'Reilly's also. I think there is a deal on here somewhere that has all the code listings, if I find it I'll post it here for you.
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Unread 04-28-2012   #4 (permalink)
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Quote:
Originally Posted by NW Drake View Post
For an 89 lx 5.0 ho code 91 one is one of the o2s is lean I forget which one. But go to www.fordfuelinjecrion.com they have code lists there

I think thats www.fordfuelinjection.com

And that's the list I was referring to in my previous post.
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Unread 04-28-2012   #5 (permalink)
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KOEO, KOER, CMM and balance test codes 2 digit and 3 digit
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Unread 05-05-2012   #6 (permalink)
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It's the o2 sensor. around $40 at autozone or around $50 at latemodelrestoration.
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Unread 05-05-2012   #7 (permalink)
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it could possibly be the o2 wiring, not just the sensor

quick way to check it is swap the o2 sensors..put the right side on the left pipe, and vice versa..plug them in and run the codes again..if you now get a code 41 and the 91 is gone, then its the sensor..if you still have the 91, then its wiring...
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