Vibration troubleshooting.

[Blackened300a]

Since I got my car back I been noticing a vibration in Park and in drive. I feel it in the seat. The engine don't miss or have any running issues, just the annoying vibration. Tomorrow I'm going to check all my coil to plug connections thinking that maybe something isn't making a good contact at idle and works fine under throttle. Im also replacing the UD pulley next week when the new one arrives. Im also wondering if a coil is starting to go bad and would act strange at idle but work under a load. I don't want to start spending money for stuff until I know for sure what Im looking for.

Any ideas or past experience?

[gdsqdcr]

Vibration or miss? When I think of vibration, I think you are rolling along. A bad coil would cause a miss ...

Anthony

[Blackened300a]

Vibration or miss? When I think of vibration, I think you are rolling along. A bad coil would cause a miss ...

Anthony

Vibration,the engine is firing fine under throttle. Just seems like its firing on 7 cyl at idle, that's how bad the vibration is.

[gdsqdcr]

A friends car had a strange vibration at idle (i think under load as well but can remember), and it ended up being a power steering or alternator pulley that had gone bad. Ever opened the hood and watched the belts go around? We found it cause we were looking at wires/plugs and noticed the belt 'waving' at us.

Anthony

[Blackened300a]

A friends car had a strange vibration at idle (i think under load as well but can remember), and it ended up being a power steering or alternator pulley that had gone bad. Ever opened the hood and watched the belts go around? We found it cause we were looking at wires/plugs and noticed the belt 'waving' at us.

Anthony

I took the belt off and started the car and the vibration was still present. I was hoping it was a pulley.

[Mr. Man]

Are all the nuts and bolts on the exhaust system tight?

[Blackened300a]

Are all the nuts and bolts on the exhaust system tight?

I was thinking that too. Tomorrow I was going to put it up on the lift and take a look. I also noticed that the exhaust is a bit louder then it was but that may be due to the fresh rebuild. Its not louder in a leaking exhaust sound but a louder drone.

[Mr. Man]

As long as your poking around tomorrow might as well make sure all the nuts and bolts got tightened properly. Could be a motor or transmission mount.

[tjl006]

Do a compression test. Just makes sure all cylinders are to spec before you go looking for other things and start spending money. If you need to swap coils to diagonose I got a couple you can borrow. Any sighns of a vacuum leak? Maby IAC?

[ctrlraven]

What's your RPM in Park/Drive compared to Neutral?

[Blackened300a]

Do a compression test. Just makes sure all cylinders are to spec before you go looking for other things and start spending money. If you need to swap coils to diagonose I got a couple you can borrow. Any sighns of a vacuum leak? Maby IAC?

It has brand new pistons all around. I'm sure compression isn't the issue here but I will have that checked out if I can't find the problem elsewhere. I just purchased 8 new coils that I will replace them all with. Im wondering if I shorted the coil when the plug backed out. I had that happen the first time it backed out and replaced it the first time not this time. I have no vacuum leaks, we smoke tested the intake before I got the car back and its tight. The idle don't surge or anything so the IAC is fine.


What's your RPM in Park/Drive compared to Neutral?

900 rpm's in park/neutral 750 rpm's in drive.

[Krytin]

I was thinking that too. Tomorrow I was going to put it up on the lift and take a look. I also noticed that the exhaust is a bit louder then it was but that may be due to the fresh rebuild. Its not louder in a leaking exhaust sound but a louder drone.

Check for exhaust pipe or other component hitting the frame/body. It may not be touching with the engine off but may vibrate/move w/engine running and just be hitting enough to cause the "vibration". Under load in drive it can actually move away thus eliminating the vibration - ask me how I know!:rolleyes:

If you are still having problems I'm off Wednesday afternoon through Friday morning - let me know if you can use an extra set of eyes/ears/fingers!!

[Bluerauder]

900 rpm's in park/neutral 750 rpm's in drive.
Seems high to me. Mine idles at 650-700 RPMs in park/neutral after it warms up.

[Blackened300a]

Seems high to me. Mine idles at 650-700 RPMs in park/neutral after it warms up.

I have UD pulleys on my car. I had to bump the idle up for the alternator to charge at idle.

[Blackened300a]

Check for exhaust pipe or other component hitting the frame/body. It may not be touching with the engine off but may vibrate/move w/engine running and just be hitting enough to cause the "vibration". Under load in drive it can actually move away thus eliminating the vibration - ask me how I know!:rolleyes:

If you are still having problems I'm off Wednesday afternoon through Friday morning - let me know if you can use an extra set of eyes/ears/fingers!!

Thanks Paul Im bringing it back to the shop that put the engine in to check it out.
The vibration feels like a rotation vibration. Like a fan with a blade missing. It does it in park and drive. I made a call to the engine builder and it was compression tested during assembly so the pistons are dead on. That leaves a bad coil, the exhaust rubbing or the balancer is shot. I do know a little bit of the rubber is coming out of the dampner and I also know that we dremeled away some of the pulley area on the back of the dampner when it hit the front cover. It may be unblanced and thats throwing it off or the exhaust is rubbing something. Laying on my back I noticed that the exhaust is very tight. It has no give at all. I was able to at least shake it a little before, but not anymore. Plus I noticed a louder exhaust drone. That may be due to the new engine. Otherwise it don't hesitiate, it runs smooth while driving, and Im feeling it in my seat not the steering wheel.
Tomorrow the new coils go in to make sure thats not a issue the the car goes on the lift to be checked out. Hopefully next week the new dampner will come in and ready to install. If all that checks out then I don't know what to do.

[Krytin]

Thanks Paul Im bringing it back to the shop that put the engine in to check it out.
The vibration feels like a rotation vibration. Like a fan with a blade missing. It does it in park and drive. I made a call to the engine builder and it was compression tested during assembly so the pistons are dead on. That leaves a bad coil, the exhaust rubbing or the balancer is shot. I do know a little bit of the rubber is coming out of the dampner and I also know that we dremeled away some of the pulley area on the back of the dampner when it hit the front cover. It may be unblanced and thats throwing it off or the exhaust is rubbing something. Laying on my back I noticed that the exhaust is very tight. It has no give at all. I was able to at least shake it a little before, but not anymore. Plus I noticed a louder exhaust drone. That may be due to the new engine. Otherwise it don't hesitiate, it runs smooth while driving, and Im feeling it in my seat not the steering wheel.
Tomorrow the new coils go in to make sure thats not a issue the the car goes on the lift to be checked out. Hopefully next week the new dampner will come in and ready to install. If all that checks out then I don't know what to do.

I forgot about the damper - that may indeed be the problem.
One way or the other I believe this can and will be straightened out!

[Blackened300a]

Today I took a good look at the car and I noticed my tailpipes are under the bumper more then before. Im thinking its got to be the exhaust. That would explain the drone, no free play and the tips shoved under the bumper.

[justbob]

Did anyone have your keys recently and perhaps backed into something? I have seen atleast 3 MM's this has happened to easilly.

[Blackened300a]

Did anyone have your keys recently and perhaps backed into something? I have seen atleast 3 MM's this has happened to easilly.

I don't see any rubbing on the edge of the tip but its possible. Did it result in a droan and vibration?

[CBT]

Hey, I have the same issue, had it for months now. Yesterday, I get the ol' familiar pulley squeaking noise, got the WD-40, popped the hood, the first pulley I blasted was the idler/tensioner pulley, squeak stopped AND I noticed it was shaking back and forth slightly with the annoying vibration. I'm going to change that sucka out in a couple days. And the belt. And the coils. And I Seafoamed it today.:D

[RacerX]

I been noticing a vibration. I feel it in the seat.
That's what she said!:banana2:

[RacerX]

Hey, I have the same issue, had it for months now. Yesterday, I get the ol' familiar squeaking noise, got the WD-40, popped the zipper, the first object I blasted was old and dusty, squeak stopped AND I noticed it was shaking back and forth slightly with the annoying vibration. I'm going to change that sucka out in a couple days. And the belt. And the bath oils. And I foamed it today.:D
Fixed it for ya!!!!

[CBT]

Fixed it for ya!!!!
Muhahahaaa! That's brutal, man. I'm not that old. :geezer:

I'll post up after I swap all that stuff.

[DEFYANT]

I vote Harmonic Balancer / Dampener. Any damage to the fly wheel or TQ converter?

[justbob]

I don't see any rubbing on the edge of the tip but its possible. Did it result in a droan and vibration?
Sorry Paul, I got busy all of a sudden. The owners have not complained about it at all, but it seems that they sure do push forward very easilly, I believe right where they turn to go up over the axel. But yes, this would definately be cause for a completely different feel and sound in harmonics for sure, no doupt about it.

[Blackened300a]

Hey, I have the same issue, had it for months now. Yesterday, I get the ol' familiar pulley squeaking noise, got the WD-40, popped the hood, the first pulley I blasted was the idler/tensioner pulley, squeak stopped AND I noticed it was shaking back and forth slightly with the annoying vibration. I'm going to change that sucka out in a couple days. And the belt. And the coils. And I Seafoamed it today.:D

I pulled the belt off and thought I could isolate a pulley, but it felt the same. Seeing my tips are shoved in and that the exhaust droans louder then before, I'm thinking the exhaust is rubbing something.

[CBT]

I pulled the belt off and thought I could isolate a pulley, but it felt the same. Seeing my tips are shoved in and that the exhaust droans louder then before, I'm thinking the exhaust is rubbing something.
I replaced my belt tensioner and all coils today, car fo sho seems to run better. Idle is up, seems peppy-er, but I didn't dog it because it was around 9 tonight when I finished. NO MORE VIBRATIONZ!!! Also, the Ford dealer parts guy could not find a Marauder belt tensioner listed, so I said give me one for an 03 Mach 1. It is slightly different. The pulley is the same diameter, but the wall is thicker. And where the Marauder pulley has no guard to keep the belt from walking off the side (how you would manage that, who knows), this one has a neat little tab. I took pics, I will post them tomorrow.

[Blackened300a]

Nope!! Try again!!

[musclemerc]

Thats good news.

[Joe Walsh]

Well today I threw the car up on the lift and exhaust is not touching anything. I used a pry bar and pushed the tip back past the bumper to eliminate the droan a bit. I did notice while running that my idler pulley had a slight wobble and when I removed it, I was turning it on my finger and felt like something was inside the bearing. I replaced it with a new one and it killed the vibration 80%. Next week Ill be replacing the balancer and that should completely kill the vibration all together.
Im finally happy to drive the car without it feeling like Im sitting on a washer machine with a un-even load. :banana:

Glad to hear that you are tracking down the problems Paul.

Now....I'm waiting for the "TWSS!" post.

[Blackened300a]

Ok for those keeping track. I've been tracking down a vibration at idle that's irritating.
Here's what I did in a attempt to fix it....

New vibration dampener.
New Flexplate
New Idler pulley
All new coils with GMS connectors.
Removed belt and felt no difference.
Smoke tested the intake and did a vacuum leak test. Both tests passed.
Complete transmission flush.
Checked and double checked the exhaust for rubbing.
The engine builder did a full balance of the engine and new crank and that all came up perfect.

Today I started the car after it sat for a week and it ran smooth as glass until I put the car in gear. Then I felt the same very slight vibration and it did it the entire time I drove the car. It don't affect the performance, no hesitations or anything like that and its a lot less then it was when I started trying to track it down, but its still there.
Im thinking that its either converter shudder. I had a slight shudder when the car was in park or neutral when I changed to the PI converter, but it would be smooth once I put it in gear. Or my tune is really off. I've noticed a lot of black soot on my tailpipes since the rebuild. I could clean them then drive home 3 miles and have black around the edge again.

Any ideas?

[Krytin]

The soot build up is a little bit too much too soon - you might be running too rich which could cause a rough idle. The torque converter shudder sounds possible as well. When I got my XCall II the canned tune had the idle turned up (I didn't ask for that but got it anyway :( ! ) The idle was rough/shuddered until I turned it back down.

My next items to check would be the A/F ratio & fuel/timing tables as well as idle speed in drive.

Good Luck!

[Blackened300a]

My idle speed is the same as it was when Sal set it back in 2006. 800 in drive and around 950 in park. I feel it more when I put it in park, but its gone when I rev over 1000 rpms. That's why I'm ruling out a balance issue. No idle surge and the throttle drops right back down after a rev so vacuum leak isn't a issue. Plus the brake pedal feels better so I definitely have no leaks. I do need a tune so I guess that will be the next attempt at a solution.

[Mr. Man]

I've been following this thread on and off. Did you check and see if the motor mounts are tight and any other mounting points while your at it.:)

[Blackened300a]

I've been following this thread on and off. Did you check and see if the motor mounts are tight and any other mounting points while your at it.:)

First thing I checked. All mounts are tight and in one piece.

[Siege]

Did you ever resolve this issue?

[Blackened300a]

Did you ever resolve this issue?

My tune was off and it was running lean. After the tune the idle smoothed out and ran great. When I installed the headers recently the idle was slightly off again because its lean, but I have a tune update that should smooth it out. Also the crappy gas I put in the tank made it idle worse then ever. Octane boost smoothed it out.

[Siege]

Thanks for the update! I'm experiencing the same issue and have ruled out everything you listed as well.

I'll try loading the stock tune tonight to see if that affects the vibration.

[Blackened300a]

Thanks for the update! I'm experiencing the same issue and have ruled out everything you listed as well.

I'll try loading the stock tune tonight to see if that affects the vibration.

That should help it out, I also noticed that the winter blend gas will make it idle a little rougher then usual.

[Siege]

I hadn't even considered the change to winter blend! Thanks for the additional possible cause.