My 03 has a rough idle mostly when up to heat would the EGR cause this? I replaced the feedback hoses and a tube from the manifold was full of carbon it now has 250,000 miles it is a 5.4. How could I clean the EGR?

 

Take the EGR off and clean it by spraying brake cleaner in it and let it dry. Make sure the cleaner goes in the ports and shake it vigurously to release the carbon deposit.

 

in the exhaust manifold?

 

No...take the actual EGR valve off the air plenum...just right-aft of the throttle body.

 

okay. What about the carbon in the exhaust manifold when I replaced the feedback hoses one of the tubes from the manifold was full of carbon I was in a hurry ( it was like 30 outside )

 

Bad Info right there. The EGR is not serviceable. You'll compromise the diaphragm very easily. Whom ever suggested this to you doesn't know what they are talking about.

 

Just test and confirm operation. If bad, replace it. I wouldn't waste time on bogus info, just do it correctly.

 

Or would a dirty IAC cause those symptoms? The carbon was lodged into the tube for the egr ( where the feedback hose goes away from the throttle body ) I am pretty positive that it blew out when we got on it. ( white smoke out of exhaust for a second or so ) it seemed like it ran better after that.

 

Replace the egr valve if it tests bad. Never attempt to clean a egr valve. Also the egr passage in the TB elbow may be plugged up.

 

Ive cleaned mine twice a year like that for 3 years and never had issues...again ol' Brewsky thinks he's seen and done evrrything...loser...dont dismiss ideas because it wasn't yours.