Rough idle,Vibration feeling

[fishnmaine]

This might be hard to pinpoint...I'll try to explain this as best I can.....This problem just started in the last 3 days.....It has been idling a little rough in gear when stopped at times......but when I'm driving seems fine....I did have an issue a couple of days ago it took me twice to start it....first time it did this.....But I notice this....from a cold start idling at about 1000 rpm I get this rough idling vibration feeling when warm to about 700 not as bad or almost disappears ..... when warm I rev it up from 800 to about 1300 rpm I get this rough idling you really feel it thru the truck but when revved a little above 1300 rpm it disappears....When I keep fluctuating the idle sometimes it drops to almost 400rpm then pick up normally to 700.....I hear allot that the IAC is always the culprit......But I hear no hissing thinking it might be a vacuum leak and I checked all hoses best I can no disconnection....Sorry for the long explanation, But I normally fix things myself to avoid the garage....

 

[wicsmith1997]

Mine does something similar to this. Only does it when its first started after sitting for a few hours. Goes away once warm.

 

[03_Sport_Trac]

I havent had this happen to me, but a good friend of mine had something similar to this happen to his gmc. It turned out to be a bad coil pack/spark plugs. It was making it misfire causing a rough idle. Try replacing your spark plugs first and see if that helps. Thats all I can think about.

 

[ncranchero]

Any "check engine" lights or code? The IAC valve and the front PCV tube elbow are trouble points on these trucks. You can clean the IAC to see if it helps. Check the underside of the PCV elbow(that's where they split) but it usually throws a lean code when bad. You won't hear any hissing.......

 

[fishnmaine]

ncranchero,

No engine lights as of yet and I didn't have any codes checked either......But today I know of one thing 1000 rpm is the worst you can feel the vibration in the truck and when I'm leaning over the engine....it's hard to tell if it's misfiring.
But when I'm driving down the road it's fine.....runs smooth.....at idle 600rpm don't really feel it.... in gear or not don't....1000 to 1500 you feel it....now if I tack it further maybe a little rough hard to tell.....I did check all the hoses all good.....I will check the PVC....I'm hoping it's not internal because it only 62000 miles....This wasn't a gradual thing it just happen 3 days ago out of the blue.

 

[ncranchero]

If it's most noticeable when you put a load on the engine, @ around the rpm's you mention then it's a good chance it's a spark plug wire. My F150 gave me a fit until I narrowed it down to that. Get the codes read and see if there's any P030x codes pending or current.

 

[fishnmaine]

It's most noticeable in neutral at a 1000......When I hold it in drive and tack it to 1000 less noticeable....I'm going for an inspection sticker tomorrow and I will ask for a code test.....it'll be nice if its just wires....but usually i can diagnose that.....but that cars of today..

 

[fishnmaine]

OK went to the garage today did a extensive code test....and nothing....he seems to think also could be the plugs or wires....notorious for fords he claims.....mention the problem probably isn't bad enough to throw a code yet...I'll do the wet test on the wires tonight.....maybe I'll be lucky to see an arc...

 

[fishnmaine]

Wet test OK no arcing.....but I did notice some smooth gouges on two wires pretty deep I thought for sure it would arc from there....it was rubbing on some tubing in the back side and wore out the wire a bit...could that do it if no arcing?

 

[fishnmaine]

Plugs and wires replaced runs smoother while driving on the road.............BUT,
still have the fluttering at 800 to 1200 rpm on idle....don't feel it below 800 and don't feel it above 1200.......lost for words right now... No codes..No engine light.....hoses seem fine unless I'm missing something.....Any ideas?????

 

[Grolli]

contaminated fuel? little water from condensation with the change in weather? could try HEAT or water removal additive in the tank.

 

[fishnmaine]

I thought about that........but why would it affect only in that range of RPM's

 

[fishnmaine]

Cleaned the IAC tonight and throttle body..........still the same......can a coil be the problem even while driving no symptoms......everything I read all comes down to IAC or wires,plugs,and pvc hose......But mine is fine.....I like to remedy this myself.....like the challenge...but I'm at a dead end...

 

[WatchThis!!]

I'm not a gearhead but the vacuum tube is the usual culprit for me; I did have one car(years ago) with similar symptoms and it turned out to be the timing belt.
My 01 has started to get a rough idle recently too. Not in the range yours is and I only see the RPMs drop(800 or so to about 500 then back) when stopped.
If you're really stuck I'd take it to a shop for diagnosis, then get the parts and do the work myself.
.

 

[swetrid]

2004 Explorers with 4.0L SOHC have bad crankshaft pulleys/balancer that cause a rough idle almost like a miss. If you shut the car off and reach inside the balancer you will feel a loose piece inside if it is bad.

 

[fishnmaine]

OK is this an easy fix??......

 

[fishnmaine]

Well I checked the crank pulley and in the middle of there is a hole and inside feels like a rubber piece and I can move it a little...is this what your talking about??

 

[sickwilly]

Mine smoothed out after replacing the fuel filter. At least with the 2005, the fuel filter is an every 30,000 mile replacement item. You are due for your second one anyway, so go for it.

I also find mine seems to run better, smother if I run an occasional tank of E85 through it. Not when on the E85, I see no change with the E85, but afterward when I get back to real gas.

 

[swetrid]

If the piece in the middle moves it is definitely bad. Not real easy to do since you need harmonic balancer puller and it is very hard to get the crank bolt loose.

 

[fishnmaine]

Some people say this pulley can disintegrate and cause major damage....Isn't that a bit extreme this is a steel pulley all around....How can a rubber piece do that...unless i was misled....