I have a 98 Prelude SH. It is currently running on a 94 Civic ECU. I got a prelude Ecu yesterday and when I hook it up my car will not start.

Here is the ECU # 37820-p5p-l04-097-302948 Is there any reason why this one is not working?

 

You need to disable or reprogram the immobilizer. Your Honda dealer should be able to do it.

 

First off, why did you put an ECU from a Civic? Those are completely different motos. Did it even work?

Second, you're probably have to take it to the dealership and have them reprogram your ECU system in your car now. Are you sure you have the ECU for an SH model? If you do need one, I have one sitting in my garage. Here are pics