High idle problem.

I have a 1988 2.5L 4 cylinder engine. I disconnected the old air filter and installed a 10" disc filter in it's place, but now the idle went from around 1.2 rpms to 2.2 rpms. Is there a way to lower the idle or would it maybe be a vaccum leak problem? I should mention on start up it goes up to about 3 rpms then settles down to about 1.8, but the idle goes up to 2.2 when I start driving and stop at a stop light.

Could be a vacuum leak(EGR) or one of the sensors is having issues. Are there any error codes?

Did this all happen after the Change? Wasn't there a vac line going to valve in the air cleaner, to direct warmer exhaust air during a cold start? Plugged it?