What is causing my sport to vibrate?

[njkev7]

What is causing my sport to vibrate?

At startup the truck is fine. When I drive and come to a stop. It starts to vibrate lightly but enough to feel. I asked my mechanic and he say Ford Trucks are like that. My question is does everyone have a vibrating truck and what could be causing it. Also, the idle is a bit jumpy, looks to go between 500 to 1000 rpms. I just did the tune up and ran fuel injector cleaner with premium gas. All filters were replaced and pcv was replaced also. It’s a 99 sport 4.0 SOHC with no check engine light.

 

[Spdrcer34]

A bad IAC, or Idle Control Valve can cause that. And that is the first place I'd look.

There are a few threads here to look at. They cover everything from their Location, to cleaning them. And their Replacement.

Just make sure you search for write-ups that cover your particular engine. As their locations are very different.

Ryan

 

[alohamonte]

i had similar problems with my X and it turnd out to be dirty injectors. i regularly ran sea-foam through the pcv and gas tank, but the injectors were heavily soiled. runs perfect now.

 

[njkev7]

i had similar problems with my X and it turnd out to be dirty injectors. i regularly ran sea-foam through the pcv and gas tank, but the injectors were heavily soiled. runs perfect now.

How effective would sea foam be if i just ran it though the gas and not in the PCV.

 

[njkev7]

Ok, so I replace the Air Idle Control Valve and it's still vibrates. I been running super and a few bottles of injector cleaner. But its still vibrating. I replaced the plugs and wires with motorcraft plugs and napa belden wires. What could be causing this. Sometimes when I drive if I give gas it idles down than goes up.

 

[ThePhoenix]

could be an intake gasket leak? or vaccuum right?

 

[gijoecam]

could be an intake gasket leak? or vaccuum right?

Lower intake manifold gaskets would be where I place my money. Common problem that's getting more and more common as these vehicles age, and it gets worse in cold weather (like we start seeing in the northern latitudes this time of year).

-Joe

 

[njkev7]

What can I do to make sure thats it. Also, I have the tools and the time, how do I replace that. Any step by step diagrams?

 

[gijoecam]

What can I do to make sure thats it. Also, I have the tools and the time, how do I replace that. Any step by step diagrams?

Search and yee shall find. There is a how-to with pictures on the site, and TONS of posts on the issue.

 

[ThePhoenix]

tons and tons. good luck...but its easy if you can turn a wrench