my e350 the check engine light code p1506 replace it but still have code

What is your question?

I replace the IAC and it's still giving me the same code. Now it's starting to run a little bit rough and like losing power I've changed everything that I can think of air filter fuel filter. I am baffled needing some help to figure out what is wrong with my van

What makes this problem better or worse?

It also has a high RPM at idle

How long has your 2002 Ford E-350 Econoline Club Wagon had this problem?

A few weeks