My 06 5.4l has been shaking at idle recently. Its noticeable in the cab but its not a violent shake. More noticeable when your looking at the motor. The motor seems to shake, smooth out some then shake again and repeat this in roughly one second intervals. Is this normal with the 5.4? The motor is quiet and is not making any strange noises. Once I give it throttle the motor runs fine and acceleration is smooth. Anyone elses motor have the same symptoms or any ideas why its doing this. The truck runs great otherwise just worried this might lead to other issues down the road. Truck has intake exhuast and tuner. I switched the tune back to stock still had the same shake.

 

How long did you run it at stock? Do a search for rough idle. It seems to be a common problem with 04s and up. Some do, some don't.

 

Tps

 

motor mount ?

 

I have a 04 f150, 5.4 engine. tow a boat. pulling boat out of water on super steep ramp i cracked a top motor mount. i noticed a idle shake like you describe after that. could not see crack where mount attached to cylinder head. mechanic could and showed me. it was a real zoo and they had to pull engine to repair. but they put it all back together with no spare parts and runs great now,, no shake,, this was about 3 yrs ago,, under warranty,, thank god,, when they pulled the motor i had them change the plugs and put new in with anti sieze grease right away. you might just luck out and have it be gas, ect,, good luck,,jop

 

I searched and found alot of information about dirty throttle bodies, took mine off and it was clean. Could be a motor mount didn't even cross my mind. I still have a thousand miles till my bumper to bumper warranty ends just hate taking it to dealerships in my area. Where was the motor mount located?

 

don't panic until they tell you it is the mount,, from what i understood they eliminated throttle/gas problems and started looking. There are 2 mounts on the bottom of the engine on the frame,, these would of been piece of cake to replace,, then there are two bars on top of the engine. They connect to the cylinder head and also stabilize the engine on both sides. This is what broke on me. I think it must of broke the mount (which was part of the cylinder head) for the rod. All i know it was a good week before i saw my truck again. I am sure it was just too much pulling the big boat up that incline on the ramp. faulty mount ? me too much gas ? who knows. But the motor should not shake,, mine is nice and smooth. Let me know what they find,,jop