So, this is my 3rd F150, '98, 02, now 2003 Lariat 4X4SCrew with the 5.4, 150K miles and runs perfect. Sat in the driveway for about 4 days. Went to start it up and it immediately backfired and then proceeded to tick or knock louder than normal...idle is sluggish, then drops off like it wants to cut off. Has never happened before. Have no clue why this happened. Any ideas as to the issue before I take to the Ford shop?

 

Check engine light on?

 

No sir......no check engine light... at least not yet...

 

Just a guess here but how has your weather been? It went from 36 to 64 to 26 degrees within 30 hours here and I had some problems with my Edge. Worked itself out and I took it as condensation from the short, warm weather. Everything was covered in condensation. Had to squeegee the inside of the cars windows.

 

Pretty normal weather for coastal plains NC... no major swings in the last week...actually been average temps..

 

Check and see if you blew a plug or 2 out.

 

Sounds like the EGR valve stuck open. That shouldn't happen from just sitting tho. Was it running fine before you parked it ?

I duno, worth a check. You described a a EGR hang perfectly. That's what happens when they do...throws a fit and stalls. Throw a brick at the valve or something, that might do it.