I've just swapped a 96 jdm gsr into my 96 rs. When I start my car it runs for like 2 secs then cuts off. So I have to hold my foot on the gas for a few minutes until my car warms up. But once warmed up everything is good and it idles fine. This only happens when I run my car off of the jdm p72 and usdm p72. But when I plugged my original p75ecu the idle problem did not happen. I am in a standstill so any advice would be much appreciated.