The following table will help you determine which MEFI controller you have. On the bottom of the controller is a sticker with a part number. The GM part numbers and MEFI ECM's are listed here:
| GM Part No. | MEFI Type |
|---|---|
| 16159919 | MEFI-1 |
| 16189069 | MEFI-1 |
| 16220371 | MEFI-1 |
| 16234539 | MEFI-1* |
| 16210729 | MEFI-2 |
| 16237009 | MEFI-3 |
| 16237019 | CEFI-3 |
| 16236999 | MEFI-3* |
| 12489488 | MEFI-3 |
| 12489493 | MEFI-3 |
| 12569494 | MEFI-4 |
| 12575479 | MEFI-4a |
| 88962717 | MEFI-4a |
| 88962718 | MEFI-4a |
| 12584052 | MEFI-4b |
| 12597744 | MEFI-5 |
| 12607802 | MEFI-5a |
| *Used by MerCruiser | |
| MEFI Type | Supported |
|---|---|
| MEFI1 | YES |
| MEFI2 | YES |
| MEFI3 | YES |
| MEFI4 | YES |
| MEFI4A | YES |
| MEFI4B | YES |