Could having the wrong ecu cause problems in the shifting points of a tranny? My tranny gave up on me recently, I had it rebuilt and now it shifts erratically. It didn't shift erratically before. Before my tranny gave up on me I had my uncle's friend check out the car because it wouldn't start. He said the car had no ecu, so he installed one. Before he installed the new ecu, it ran well, the tranny gave me no problems, but it did seem to have low gas milage. Is it even possible for the car to run without an ecu?

I have a 1993 Civic Ex 1.6L AT. The ecu that my car has installed is a 1995 Del Sol 1.5L AT ecu. Could this be the reason as to why my tranny won't shift properly? Thanks for your help.

 

welcome to the forum, yes the wrong ecu can cause the trans to shift incorrectly. can also cause the engine to run incorrectly.