Swapping ECUs for fun and profit

Post by **FireFox31** » 13 Jun 2023, 22:55

The ECU in my 1998 T5M was apparently replaced by the previous owner with one tuned by TME. I'd be interested to try a stock T5M ECU in my car to see how it performs compared to the TME one. Surprisingly, I found a local seller offering a 1998 T5M ECU. Seems like a rare part, thus worth buying to try out. However, I can't tell what tune, if any, is on this ECU (or on mine for that matter).

What's the worst that could happen by swapping in an ECU which claims to be identical to mine? Is there any value to me owning a second of these rare parts?

Post by **abscate** » 14 Jun 2023, 04:01

$100m but maybe $50 in this economy.

Post by **Chuck W** » 14 Jun 2023, 05:14

Without knowing anything about the ECU in your car, it's hard to say.

If the "tuned" one is tuned for stock injectors/turbo, swapping in a stock one will probably not pose any significant problems.

A spare 98MY manual ECU would be good to keep around.

(I just occasionally buy 98MY M4.4 ECUs, as I like to have a spare or two and I flash ours. I don't care what factory tune they are, however.)