My 5.4L has only 300 miles on it but it seems to vibrate into the cab a little more than it should. The tach needle is steady, no surging or dipping. Has anybody else noticed this and is it a concern? I'm not interested in bringing the truck back for this, as it runs great otherwise. Maybe it's just me coming from a swedish touring wagon, with much better cabin isolation.

 

2005 F150 XLT 5.4

I have the same idle problem especially on cold starts. Once I get it out of the driveway and down the street it is barely noticable except in park. I took mine to the dealer and they did an update on the computer which doesn't seem to have improved things much. I have 3750 miles on clock. The service manager told me to put 6 ot 7 thousand miles on it and it would probably smooth out. He added that there were new updates available often and to keep in touch. I was told on another forum by a tech that it might have a slight vacuum leak but gettin these guys at the dealerships to look for that is another thing altogether. If yours doesn't improve take it in. You may get it fixed and help the rest of us.
Thanks,
Mike

 

ReForder, I had an 04 scab F-150 with a rough idle. After two attempts to fix it, the dealership showed me a letter from Ford stating that they should not try to fix it, update to follow. I had the problem from day one among other problems, vibration,door panel wrinkles, etc. Ford bought back my truck in April 05 after a year of dealing with a faulty product. Hope you have better luck with yours.

 

I had the same problem. A reflash from the dealer helped some, but after time it has completely gone away.

 

Give it time. It will go away.

The 5.4 Ford motor is one one the few longer stroke motors around and they inherently idle smoother. Just need some break-in time in my experience.

 

well does the engine need more break in time than 16,000 miles? i have the rough idle and have had it since day one... i was told "its just a characteristic of the engine". well i have to say that i believe that statement is bulls@!t. i have had other vehicles that didn't shake while stopped and idling. whether it be in park or in drive holding the brake it still trembles off and on while idling, it almost seems as if the truck is about to choke down but it doesn't. is this what everyone else has?
i don't think it is a characteristic of the engine nor do i think in time that the engine will eventually smooth out. i can open my hood and watch the engine tremble every 3-5 seconds. i just think that something that shakes like my truck does, engine tremble, like mine does , and steering wheel nibble like mine does, will not last the 6 years that i am having to pay for it. I have lost some faith in ford as to having the best quality light duty trucks on the road. sorry guys but i am not a troll. i love ford i really do, i just wish i wasn't on this website everyday looking for remedies to my truck problems and on top of that is less than a year old. thats my venting for the day.

 

I've already imagined in my head the situation at Ford service. My truck will sit there all day, i'll be out of transportation, will get the truck back with a "we didn't find anything wrong" followed by a "give it time to break in" (as you have all said) and it will be exactly the same.

The performance is fine, but if i focus hard enough I can pick up an ever so slight hesitation or stutter if i mash the gas from a stop. But that can also be tranny or rear related, so I'm discounting that. I'll wait until my first required service interval and will probably bring it in then if its still doing it. It definitely doesn't seem normal for a brand new vehicle.

 

DON'T WAIT!! I waited and when it can't be fixed and you want your money back they will charge you for milage. Let them know immediatly of your concerns. As for the rear end shutter, it's real. They can put an additive in the rear end to fix that, but thats how all my vibration problems started. Good luck.

 

re: some vibration on a 5.4 at idle. It is normal- nature of the beast. Most noticeable in F150's and Expys.

Rr Axle shudder: typical of LS axles. My '93's been doing it for almost 200k miles- hasn't failed yet.

 

You make a good point. With two 5.4's in a row I would have to say they have been the smoothest running engines I have ever had. There is defintiely something not right if they do not completely smooth out in the first 2000 miles. Smooth idle is a characteristic of a long stroke engine.

Just as a remote possibility, have you run any injector cleaner through your truck? Read the instructions carefully and make sure you use enough. I put three bottles in a while ago and some slight starting hesitation cleared up.

 

mw1063,

Just curious how many miles on your truck when you noticed that the rough idle had disappeared. This seems like it might be a break-in issue, at least in some cases. I've heard about some real long break-in periods for some Ford engines. It just seems unusual for a new engine. The 5.0 in my 95 Bronco idled smooth as silk from the get-go.
Thanks,
Mike

 

The 5.0 in your bronco was a classic tried & true 302, OHV engine, most likely with a heavier cast iron block and heads. I think that has a lot to do with engine vibration but that's just an opinion. I've owned 302's intermittently over the last 16 years and love them, cake to work on. I think the aluminum, Overhead cam engines may be more prone to small vibration, as they don't "sit" as heavily on the motor mounts. Just a hunch.

Anyway, I am not returning this truck just for a rough idle. I know its not the axle problem, as that is a way different sensation than what's happening now. I'm gonna let her break in a bit and take it from there.

 

the tach needle will never bounce or ever show the right rpm its off some. to find this run the truck in test mode. hold down the trip reset button while turning the truck on then when the test comes up keep hitting the trip button to thumb through it.

 

I've owned three 302's over the years, and they were all smooth as glass. All the 5.4's I've driven (the wife's Expy, two F150 demos) have had a little vibration at idle, but they smooth out once underway.

 

Reforder, there was a post about that exact problem a couple of months ago. I have an 05 Lariat I bought in April and had the exact rough idle issue. I also waited thinking it was just an engine break in issue, so when I went to get the first oil change done on it last month I brought it up. They of course had to keep it overnight wanting to check the fuel injection, and wanted the engine stone cold to test it in the morning, but ended up just reflashing the computer and that definitely helped. I Knew it was the computer after reading posts here, but of course the customer is never right!