Previously dynotuned ecu can i add a utec on my 03?
so heres the situation. i bought my car previous owner tuned it. no piggy backs no acces port with it or anything i assume dynotuned. i recently put in an 04 donor longblock motor when my original spun bearing lost cylinder and ever since the swap that was in and out in a few short hours being a full longblock minus the turbo ive had some issues with boost fluctuating the dyno shop i have locally tells me most likely needs to b tuned to that motor. now i was offered a utec system for 02/03 for trade for struts i got on craigslist. i want the utec system but will my already malfunctioning ecu motor combo is a question can i plug in and fix the issue or do i have to have my ecu reflashed or retuned to use the utec??
05 2.5 RS
90 Celica alltrac turbo
90 Enfini RX-7 JDM FC3S swap