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Something expensive happened...Help please.


polarisman14
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I'm at my wits end with this car. After 2 years I finally have a running and driving MPI car and now this happens. I was datalogging for Scott and gently accelerating away from a speed bump. I hear/feel this "pop" immediately followed by vibration. I already have every poly mount (engine, trans, suspension, etc.) that Stedebani makes, so the car had some vibration to begin with...This was WAY worse than that. Shaking the header panel, grille, dash, practically shaking the fillings out of my teeth.

 

I'm trying to find out what it is now...Based on what I saw browsing the forums it's either a rod bearing or possibly a loose flywheel or something...

 

I did a compression check and it's 120-125 across the board. Pulled the valve cover, everything under there looks OK. No broken valve springs, etc. Checked the engine mounts, those are tight and fine. When I am cranking the car over there is a slight clacking and sometimes when I shut the car off it clacks as well. At idle and across the RPM board (don't worry, I'm not revving it up or anything..I just mean at lower rpms) it vibrates like crazy so something is definitely wrong.

 

My real issue is that I am TOTALLY tapped out financially and then some since I got the car back from paint and body work, tuning was supposed to be the last part of this project and I was ready to enjoy it for the remainder of this season...

 

What other information do you guys need to help me figure out what it is?

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I would say no because it happens at idle in neutral, I'm pretty certain it's something in the engine.
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Yea, the first impression I got before finishing reading through your post was maybe a knuckle on your driveshaft but after finishing... Idk man. I wish you the best of luck and hopefully you find that it is something minor and you can still enjoy it.

 

Allen

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i have never personally seen a rod bearing cause a vibration the way you discribe it

normally you get a knocking noise with rod bearings

 

now a thrown rod will cause a vibration but the engine should be making all kinds of noise at that point or even locked up depending on where the rod ends up

 

im thinking mabie balance shaft

 

does the car idle ok ???

 

if you lightly rev it do you get any kind of knocking noise

 

or if you raise the rpm's at idle tell it starts to make the knocking noise hold them steady there and pull 1 plug wire at a time tell you find the one that makes the noise/vibration stop that would be your problem cylinder

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I'll do my best to answer the questions in the order they were received.

 

I'm thinking it may have been a balance shaft as well. I was just reading in the FSM about how to adjust it by removing the plate that's under the water pump pulley and adjusting it with your finger then reinstalling. I'll look into that.

 

D, I'm also planning on removing the inspection cover and taking a look at the flywheel. I saw that Indiana had put some advice on how to check and see if that is out of balance or loose.

 

Sleeper, I was thinking it could have been the pilot bearing but I thought that was part of the clutch assembly that would be stationary unless the car was in gear? However when I owned my Focus the pilot bearing did make noise but that was only at idle and went away as soon as there was any load on the engine or when the car was in gear.

 

RobH, I'm thinking (and praying) it isn't a thrown rod...If it was I would think it would throw the compression numbers off for that cylinder not to mention make a hell of a racket (moreso than this...once the car is idling it seems pretty smooth, just vibrates more than normal).

 

If I rev it there's some noise but it's hard to isolate where it is coming from since the vibrating makes everything loud. It's almost like what I would expect excessive piston slop or something to sound like. I'll check into pulling the plug wires as you suggested. I just don't want to have the car running any more than I need to and do even more damage.

 

Apate, The oil pressure didn't seem to change.

 

UCW, does the clutch itself spin when the car is in neutral or is it at rest? Never really thought about how the clutch, fly, and pressure plate worked together to move the power from the engine to the tranny.

 

Tech, injectors are all plugged in and at least all making noise. This doesn't necessarily mean they are all working right, but they all sound the same with the stethoscope so it should.

 

Larry, I didn't drain the oil yet. When I pulled the valve cover the oil looked pretty clean from what I could see but that isn't to say there wasn't a ton of metal in the pan or anything.

 

Johnny, I pulled on all of the pulleys and stuff to make sure there wasn't any wobble or play and everything looks to be intact.

 

This really blows. Even if I figure out the problem, I can't afford to fix it.

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UCW, does the clutch itself spin when the car is in neutral or is it at rest? Never really thought about how the clutch, fly, and pressure plate worked together to move the power from the engine to the tranny.

 

 

The clutch pressure plate is bolted to the flywheel and moves at all times when the engine is running. The friction disk and input shaft of the transmission moves any time the engine is running and the clutch pedal is not pushed to the floor. Having the car in neutral just means that inside the transmission the moving input shaft is free wheeling, not couples to the output shaft via the gears in the transmission. Pushing the clutch pedal down disengages the friction disk from the pressure plate and flywheel so it slows down / stops moving allowing you to shift gears.

 

Keith

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^^OK thanks. Makes sense now why the clutch, flywheel, pressure plate, or t/o bearing are possible culprits. Before I just thought it could have been the flywheel or t/o bearing.

 

As that is the case, does the flywheel inspection cover actually give you enough access to tighten those bolts should they be loose or missing, or just give you the ability to see them. I have a feeling fixing this issue is either going to involve pulling the trans or the engine itself.

 

I'm currently uploading a video. Unfortunately the clacking on startup and shut-down wasn't there, but you can see how much vibration there is. It only clacked once but that was right when the engine started so you can't really hear it as well. When I was replicating it yesterday it would make noise when cranking and during shut down.

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Sounds more like one of your mounts, be it engine or tranny. I know you say they look OK but until you try jacking the motor up you really won't know. If there's enough vibration then the clacking can come from vibrating heat shields or other stuff shaking around.
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Where should I jack it up from? Obviously not the oil pan, but there aren't many good places to jack the car up from underneath it. Is the idea to just jack the engine up enough to release some of the weight of the engine/trans on the mounts, then try starting it to see if it made a difference?

 

Even if it were the engine mounts, why would the engine itself be moving around that much to cause such an excessive vibration?

 

I'm gonna see if pushing the clutch in makes a difference as with some people they say it did. I'm also going to remove the flywheel inspection cover and try lightly prying on the flywheel to see if that's loose.

 

Lastly, I may take off the cover plate and try to re-tension the silent shafts to eliminate that as a possibility. If none of those things (including jacking up the engine) makes a difference, I gotta suck it up and pull the pan, expecting the worst.

Edited by polarisman14
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Oh, and here's the video I took earlier...

 

http://s512.photobuc...nt=DSCF0601.mp4

Edited by polarisman14
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Welp, this isn't looking good. Don't know how long it should take to build up oil pressure or how high it should be at idle, but right now at idle (about 800rpm) the needle is at or under 1/4 of the way up the oil pressure gauge, and I notice on cold starts it takes a little while to even build to that point. This isn't good.

 

I bet I know what happened, too...In the beginning of the tuning process I had fuel but no spark so it was probably dumping fuel into the combustion chamber and some of it got into the oil. Now that it's running correctly that gassy oil is wreaking havoc on all bearing surfaces, etc in that engine. The pop was probably one of the rod bearings letting go, and all of the vibration is likely due to the slop in the bearings that the ineffective oil caused.

 

This is all hearsay until I have a chance to get the car in the air and pull the pan to see what the real issue is, but it seems like a safe bet to me.

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don't use the stock gauge to diagnose anything, it's just a slow responding guess-o-meter. Get a real oil pressure gauge,you'll be surprised at how differently it responds.
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oil pump drive gear/ balance shafts, might have put the shafts out of time? no woodruff key in oil pump gear? Edited by Dad
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^^Yeah I was thinking maybe it was the balance shaft and something else, I know the BS and oil pump are hooked together so that's a possibility. Would I be able to figure anything out by pulling the inspection hole cover?

 

Anyone care to elaborate on Scott's suggestion of jacking the engine up from somewhere (where?) to test the engine mounts as a potential culprit?

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