Open the hood

Facing rearward looking towards the windshield. Focus to the upper left hand (passenger side) you should see a grayish soft foam cover, remove the (3) black plastic buttons that are on top. Pry out the plastic tab centers to remove plastic tabs.

Remove insulated foam cover.

Now you should see a hard plastic cover, remove the (4) top screws to remove cover.

You will see the ECU box attached to a wire
harness.

Remove engine computer "2". This is the ECU that you need.

ECU labeled "1" is the automatic transmission computer.

Pull it out, the ECU just slides out.

If you are ordering a E-PROM, write down the last (3) #s of the BOSCH #s.
example: 0-261-200-xxx

Do not disconnect harness as yet. After ECU is removed completely, disconnect harness

READ THIS PROCEDURE FIRST BEFORE PERFORMING ANY FURTHER WORK. COMPREHEND AND UNDERSTAND. IF FEEL UNSURE, CONSULT A PROFESSIONAL. DAMAGE TO THE ECU CIRCUIT BOARD CAN OCCUR.

93-95 ECU #413, 506

On the top side of the ECU you should see(2) stickers and 6 little bolts.
Do not remove theses bolts.

You should see 6 tabs. Bend the tabs so you can slide the cover up from it's original place.

Now you should see the inside of the ECU.
In the upper right, there's a white cover on
top of a chip, looks like a "H".
HERE LIES THE E-PROM underneath.

NOTICE: Before removing the E-PROM, note the divot on the side of the E-PROM

CAREFULLY take off the chip, use a de-magnetized flat head screwdriver (thin as possible) and SLIDE it CAREFULLY under the chip.
Slowly push the E-PROM off its original place from the bottom.

Install the AA E-PROM, aligning the divot to the same side as the old one. Carefully insert the e-prom pins into the holes

Forcing the pins will only break off the tabs
making the E-PROM useless.

92-93 ECU #402,403,413

Looking at the ECU from top with the BOSCH labels. There are (4) torx screws.

-Remove these screws. With the cover off, remove the white plastic cover.

-Flip the ECU over, upside down. There is a small white plastic pin in the middle. Remove this pin.
-Flip the ECU back, facing right side up.

-Hold the ECU with the plug housing facing away from you. Grip the ECU metal mounting ears with both hands and push up on the upper printed circuit board where the 2 plastic pedestal connects to the circuit board.

DO NOT PUSH ON THE CORNERS OF THE UPPER CIRCUIT BOARD. IT CAN BREAK.

-Be careful, the circuit board should
unsnap, leaving the front section still attached to the plug housing.

-Gently slide the circuit board away from the plug housing. This is the hardest part, but it will separate.

Now you should see the inside of the ECU.
In the upper right, there's a white cover on top of a chip, looks like a "H". HERE LIES THE E-PROM underneath.

NOTICE: Before removing the E-PROM, note the divot on the side of the E-PROM

CAREFULLY take off the chip, use a de-magnetized flat head screwdriver (thin as possible) and SLIDE it CAREFULLY under the chip.
Slowly push the E-PROM off its original place from the bottom.

Install the AA E-PROM, aligning the divot to the same side as the old one. Carefully insert the e-prom pins into the holes

Forcing the pins will only break off the tabs
making the E-PROM useless.