Question about 1990 Ford F250

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Location of engine code plug 1990 F250

Where is the engine code test plug located on a 1990 Ford F-250?

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  • geoelbell Dec 31, 2008

    Guess what? My old ford code reader won't fit the test plugs- they're square! If I knew which termial was which, I could read the codes with my multimeter. Dang Fords!



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1990 was NOT OBDII, but it WAS an OBD or OBDI.
OBDII (2), was not in use until 1996, actually late 1995 they started to appear, since mandate was for all North American vehicles to have them in place by 1996!
Anyway, Communication port for OBD is under the hood for all pre 1996 Fords.
Look here:
How to retrieve codes from an OBD system 85 95 Ford Truck Club Forum
Then for Convenience, and for very little $$$, get one of these:
INNOVA 3145 Ford Digital Code Reader
You will be glad you did.

Posted on May 18, 2015

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Should be below the steering wheel close mounted just under knee board

Posted on Dec 31, 2008

  • Howard Lester Dec 31, 2008

    Just go to your favorite auto parts store and they will retrieve your codes for free.Can't do it with the meter anymore.


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Obd 2 didnt come out until 1996 have to go to parts store for obd 1

Posted on Sep 14, 2009

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