shescountry

Can anyone tell me why my 05 idles rough in park? It doesn't do it when your in gear and hold on the brake, Only in park. 05 5.4 161k miles with the ac on. It's not running hot at any time.

fenza89

mine sometimes idles rough. i have a 2006 with 80,000 miles 5.4

shescountry

I don't understand why. I have new coil packs and spark plugs, only a couple months old.

powerranger262

Something easy to check would be the foam surround around the air filter tray. It tends to dry rot and disintegrate. You can put weatherstripping witht the adhesive back on it to fix it. Search rough idle on the forum, there is a sticky for it.

j.low

With that many miles check the Catalytic Concerters. Those cause all manner of weird problems.

shescountry

I have an aftermarket intake, hasn't had stock on it in a year or so. The shop never looked at the cats when it was in for spark plugs and coils.... Is there anyway I can check them myself? Or am I gonna have to take it to a shop and let them look at them? Been debating high flows just haven't done it yet.