B2600i ECM Question?
 

I have a '93 B2600i, the ECM was bad, and I couldn't afford another (new or used) I did some reasearch and found out that the ECM's from the MPV (van's) are the same and they are $30 used instead $160. Anyway, I got one ordered, it just came today and I got it put in. I then hooked up the battery and the main relay is "chattering" (clicking really fast). When I put the old (bad) ECM back in the main relay seems to work fine. I'm assuming this ECM I just got is bad? the place I ordered it from has a warranty and I can send it back. Let me know what you think.
Thanks