Hey everyone I have a 2002 F150 with the 4.6L V8. Every morning or after it sits more than 2 hours when i start up my truck i get a small puff of smoke out the exhaust. I dont want to cause any damage to the converter by letting this persist. I also feel a slight stumble in the idle although no codes present. i replaced the plugs last summer with motorcraft oem replacement plugs. I only put on about 10K miles. coils all seam to be in great shape. Any advice would be very appreciated. Oh yea the color of the smoke is hard to make out due to the small amount comming out at startup.

 

check your tail pipe to see if you are running arich fuel mixture. if the exhaust is white in color you may have a leaking head gasket.if its a black puff you may have a bad o2 senser. but you should have a code come up. email me back and ill try to help you the best i can. james