2000 SEL odd noise at Idle

Recently(Last month) replaced the plugs and wires on my Windtar as it has 80K. Also changed the PCV and fuel filter at the same time. I just noticed it makes a different noise at idle then it did before. I don't normally drive it so I'm not sure it has anything to do with the recent changes. I'll attempt to describe the noise so I'll understand if you get a chuckle or two at the description.

It seems to idle around 800-900 rpm and has a "mutt - mutt" sound. It doesn't hesitate or want to stall but I can still hear the noise at initial accelration. There are no codes (checked at AZ today).

I used motocraft pugs with a different brand wire (don't recall off hand). I can't realy tell the location of the noise.

Any ideas? Thanks.