Are your spark plugs the original ones? If they have been replaced, what brand of wires was used? The same two questions could be asked about the spark plugs as well. If they are original and/or not Motorcraft brand, I would recommend you replace them with Motorcraft wires and plugs.

The buzzing sound could be the result of a leaf or something similar that is caught somewhere in the air intake system. Its worth a check.

You should seriously think about following up on Pawpaw's suggestion and replace the O2 sensors. If they are the original ones, its entirely possible that both of them could be dying at the same time. If your engine is running lean under acceleration, that could be the problem.

Let us know what you find. Good luck.

 

The mechanic told me that the motor was fine and had no problems. He even tested my truck. He also said that the plugs, wires and MAF sensor are fine. To me, that is all very strange.

Saturday night, I replaced the front headlights and at the same time I opened up the airbox. I found a few little round thignies(they come from trees) that were in there. So, I removed them from there. Air filter is pretty good and the seal seems fine.

Today, I did not get that humming sound. I think it has to do with the weather. Since it was warmer today, I didn't get that sound.

 

Last night I was talking with my buddy. He is pretty good at working on cars and I asked him if he could help me out on replacing plug wires and sparkplugs. He said sure.

So, this morning I got some NGK plug wires and some sparkplugs. Total of 100$. Took about an hour I guess. It went really well and some sparkplugs were not even tighten correctly. They were all very worn out.

Tested the truck out and it made a world of a difference. Better idle, no more jerking, sputtering and hesitation. I'm glad I got this fixed.

Only a little issu is when I accelerate hard and the trucks revs up, I here some rattling, like if something was shaking. Maybe a heatshield of some sort.

My buddy also hooked up my truck and no codes appeared. He says my truck is fine and has no issues.

 

Good idea to have a look at the plugs & wires & to hear the investment was worth it.

 

Yea, I am happy my truck runs well. Thanks for all the help! Very appreciated!

 

My 02 4.6 expedition started "chugging" today. Seems like it started trying to hold a steady speed at around 40 but it also did it at start up untill I reved it up. The engine light WAS on for a running lean on banks 1 n 2. Had a mechanic find a hole in the PCV line but right now no light. I also awhile back had a misfire #5 cylinder so I replaced that coil and that problem was fixed. Not sure w the plugs were done last. Iam leaning towards fuel pump....any ideas? I do my own wrenching w I can.
Thanks

 

Head gasket maybe? I know the Ranger Cologne 4.0 was known to have the #6 spark plug fooled because of a bad head gasket.

How does the coolant and oil look?