Are ECU's interchangeable?

I think the ECU is shot in my car, and I was wondering if anybody knows anything about replacing them. What I want to know is whether or not I have to replace the ECU with another one of the exact same type. Do the numbers have to be an identical match, or can certain numbers be interchanged for each other?

My car is a 1991 Talon TSi 2.0 Turbo FWD. The ECU I pulled from my car is numbered MD166260. There's another number under it that says E2T36574M. There's also another sticker on the side that says 6260 on it. Do I have to find another one with the same numbers, or is there another one that will work? If I have to be exact, anybody out there know anyone with a spare MD166260 that they're wanting to part with?

Thanks
Jon

Forgot to say that it's a 5-speed.

Would an ECU out of a 1990 Laser 2.0 Turbo FWD 5-speed work in my 1991 Talon TSi 2.0 Turbo FWD 5-speed? The number for the ECU from the Laser are MD128625, with E2T34474A written under that. Would that work in place of my MD166260, with E2T36574M written under it? The throttle bodies on the two cars are different. That means that at a minimum, the ISC Motor is different. TPS is probably different as well. What do you think? Will it work?

Thanks
Jon

they need to have the same numbers. other numbers might work but it would probably be screwy. take the cover off your ecu and look for burnt parts. you probably have a blown capacitor if you diont know electronics take it to somebody who does. hell you vcould probably take it to your local radioshack

ive got a wrecked 97 talon tsi will the turbo on that fit my 97 eclipse rs

i had the exact problem you have.... the smartest idea is to go onto ebay and type in the top number on the ecu... with any luck a bunch should come up... if not put in turbo talon ecu and find one that matches

yes u can use that turbo