Yes, the codes are stored, even for OBDI. Here is all the info I have on the Jumper Trick for OBDI cars.
... 12
.. /--\
. |----|
.. 3456
|=|
STC
Imagine that the above diagram is the Test Connector. I know it's a rough sketch, but you'll get the idea if you know what it looks like.
1. Connect a large paperclip from Pin 2 to the Self Test Connector (STC).
2. Run a wire from Pin 4 to the Positive Battery Terminal (or use a Voltmeter or Test Light as shown on
http://www.troublecodes.net/Ford/).
3. Turn Key to the ON Position to begin the Self Test.
4. Your fan will turn on, first in a low speed, and then a high speed. This is normal.
5. Codes are flashed by the CEL light. If you're using a Voltmeter, or Test Light, you'll see the pulses or flashes on those devices.
To determine a code, add up the flashes between short pauses until a long pause is reached. That is the first digit.
Then, add up all the flashes for the next digit, and so on.
Each code is 3 digits in length, and repeats twice.
6. IIRC, a code of 101 starts the test. Then there is a long pause, and then the codes stored are displayed.
7. If you have an MTX, then you'll receive the 522 Code indicating that the Transmission is not in Park (duh!)
Use the Haynes Manual for more info, but remember that the Diagnostic Connector is located in the engine bay next to the Left Front Strut Tower. The Haynes Manual I have says that it was near the Front Right Spring - This is wrong!
-Edit- I made the diagram a little nicer, but look at
http://www.troublecodes.net/Ford/ for a better picture.
