ECMLink is released as an EPROM replacement device. That means in order to run ECMLink in your ECU, you must have an EPROM model ECU.

For 2Gs ('95-'99), that means a 1995 ECU because that's the only year EPROM ECUs were available for the 2Gs. For 1Gs ('90-'94), EPROM ECUs were available every model year, but you HAVE to check yours to see if you have an EPROM model or not. Additionally, for the 1Gs, if your ECU is non-EPROM but in good condition otherwise, we do have an EPROM conversion service we can perform if you'd like.

We do sometimes have a few EPROM ECUs available here for sale, so feel free to drop us a line if you want. We provide a significant discount on these ECUs if they're being purchased along with a new ECMLink package. You can get contact information off our contacts page.

Another option is to call a few salvage yards. We've found the car-part.com site to be particularly useful for this. You may need to call around a few places before you find one willing to check the ECU for you, but you can often run up on a pretty good deal ($125-$200).

To check for an EPROM inside your 2G ECU, pull the ECU out and check the sticker on top. The sticker should have a part number on it (e.g., MD309947) with some other numbers and a letter in the lower right hand corner. The image below shows this sticker.

If the letter in the lower right hand corner is an “E”, then the ECU most likely has an EPROM. To know for sure, you can follow the same steps as outlined below for the 1G ECU.

A list of valid 2G turbo ECU part numbers follow. Note that only the first two marked in bold will likely contain an EPROM. But it's not guaranteed! Please reference this chart if you're not sure about the computer you're sending in. We have had a few cases where folks have shipped us a transmission control unit instead of the engine control unit.

To check for an EPROM inside a 1G ECU, you can start with the same label check described above for the 2G ECU. However, with 1G ECUs having so many problems internally, it's been our experience that the casing for a 1G ECU disagrees with the board inside far more often than is true for the 2G ECUs. The boards inside a 2G ECU tend to stay inside the same case. This is not so true with 1G ECUs, so a further check is required to make sure.

Open up the case by removing the screws (2 on each “side”) holding the top in place. Then remove the top casing half to reveal the circuit board. Compare with the photos below to determine if this ECU has an EPROM or not.

A list of valid 1G turbo ECU part numbers follow. Please reference this chart if you're not sure about the computer you're sending in. We have had a few cases where folks have shipped us a transmission control unit or a non-turbo model instead of a turbo model engine control unit. Also note that the GVR4 ECU (MD165810) is as close to guaranteed to be an EPROM model as you can get.

Also note that only the numbers listed in bold are possible EPROM candidates. We've never seen any of the others come as EPROM model ECUs.