72812sc300

I have an automatic 95 sc300 and I just replaced my ecu cause my other one had water damage and it was causing my car to idle high and then shut off. After replacing my ecu, car idles normal now and doesn't shut off. But now the car sounds strange when idling and it idles a little lower than usual and sounds like not all cylinders are firing. Switched out igniter and checked distributor cap and nothing seems burnt. Need some help in what might be wrong

jadu

iTrader: (42)

Is there black soot coming out the exhaust? You may also use the idle set screw to get it from idling too low.