The car shakes at 0mph

[Motorhead350]

Here is what happened: I raced a C5 on an interstate, went up to 130. He lost. When I got off of the road 20 minutes later the car would shake when it's in drive at a complete stop. Off the line it shakes too. It'll still have the power, but off the line it shakes.

It's acting just like there is a vacuum or boost leak. I went over the car for hours and couldn't find anything leaking. I went over all clamps and tightened anything that seemed loose. It threw an engine code relating to the EGR. Upon looking this code up it said this may or may not be the problem being that this code could go off as a mistake.

Tomorrow Justbob and Abdul said they would assist me. I am going to swap the EGR valve off one of their cars and see if this solves the problem. If it does I'll buy one, if not I don't know what else to look for.

Thoughts or suggestions?

Do not post if you have a problem with me, only post if you have something useful to say. I'm really tired of wasting my time reading something that doesn't help me get the problem solved. Lately there has been a lot of it. :shake:

Thanks.

BTW when the car is in park it will not shake. Same with reverse. Just in D will it be acting like this.

[BAD MERC]

Any chance you have a bad COP or lost a cylinder?

[LeoVampire]

Is it smooth while in park or nutral?

[Motorhead350]

Any chance you have a bad COP or lost a cylinder?

That's what I am guessing, but I don't know how to tell if one if is bad.

[Motorhead350]

Is it smooth while in park or nutral?

Yes. Drive is the only time it shakes.

[LeoVampire]

Sounds more like a transmission problem seeing you said it is also smooth in reverse as well.

[Motorhead350]

Sounds more like a transmission problem seeing you said it is also smooth in reverse as well.

I would think that if I was driving, but if the car isn't moving at all and it's shaking, I would doubt the transmission. Who knows though? I certainly don't.

[Go2GuyFL]

As you open your throttle, the EGR valve opens to allow more of the exhaust gas to recycle and burn prior to emissions. Sometimes they go bad and get stuck open. It will make your engine rough idle almost to the point it feels like something inside broke. You can try tapping it with a hammer to help it reset. If your car has less than 55K miles and stock exhaust, it will be replaced at no charge.

Long story ... this happened to me once with my '93 Ford Mustang.

[LeoVampire]

I would think that if I was driving, but if the car isn't moving at all and it's shaking, I would doubt the transmission. Who knows though? I certainly don't.

My guess would be the forward gear band is slipping. I am trying to look through the diagnostics for them right now to confirm my thoughts.

[FordNut]

First, did you get the tune done before you raced?

Possibly you closed up a plug gap, or busted the insulator. Both of those have happened with boosted engines due to detonation.

Check the plugs, and follow the directions that have been posted on here a million times or you'll be replacing a head for stripped threads.

[LeoVampire]

Ford says an intermediate clutch chatter in first gear can cause this.

There is supose to be a clip inside keeping this from happening but it may have snaped off if you have the 4R70W tranny.

[Motorhead350]

I'm going to Justbobs to see what's up. This sounds just like what Mark posted. I did tap the valve, but nothing changed.

Brian this was before a new tune, but I have been driving the car like THIS for over a year. Something might have finally went or it was a plug. I just changed the plus a few days ago. Hopefully it's something stupid.

[guspech750]

Good luck Dom. Hope you figure it out soon!!

[RoyLPita]

Whatever the cause is.......fix it.

[BAD MERC]

That's what I am guessing, but I don't know how to tell if one if is bad.

Borrow a laser thermometer from somebody (A/C guys use them) and point it at each exhaust outlet. The dead cylinder will be dramatically cooler than the others.

[Ktorres1]

+1 what badmerc said.

[LeoVampire]

My only concern is he says it only happens in drive and never in reverse nor park and nutral.

If it was an engine problem it should be happening no matter what gear the car is in.

But let us know what you find and take it easy on the car and don't push your luck till she is repaired.

[justbob]

Hmmm. Brian wins. Number 8.
http://i300.photobucket.com/albums/nn19/marauding4life/sparkplug001.jpg

[RoyLPita]

With that damage, get a boroscope and see if there is any piston missing off of the top near the edge.

[justbob]

I was thinking the same, but I have no means of that. I did run a compression test, all is good.

[FordNut]

Lucky. Hopefully no permanent damage. A broken ring land wouldn't surprise me, but if may have gone out the exhaust and not create more problems. But if it is a broken ring land, it will probably break some more and cause additional problems in the future. Find somebody with a borescope and make sure.

Possibly detonation simply closed the plug gap, if so it's fortunate the rod didn't window the block.

Check the ring land and get a tune.... Or go ahead and get another engine.

[bawazir]

Doms hows the car running now?

[thathotrodlincn]

Please keep us advised on your progress. Your experiences could benefit many. Good luck on your quest for a fix.

[LANDY]

Hmmm. Brian wins. Number 8.
http://i300.photobucket.com/albums/nn19/marauding4life/sparkplug001.jpg
wow! that looks pretty intense, good luck Dom.
at least the compression is good.

[Motorhead350]

I always push the crap outta this car.

It runs great now. I really feel stupid that it was just a plug and on top of that I put the wrong plugs in the car earlier this week. Now I have the Autolite double platinum plugs and they feel great. Gapped to 27 and it's just fine.

The car hasn't felt this good in years actually. It's really smooth.

Thanks to everyone, especially Justbob.

Brian, do you have a Cobra Short block laying around? If so put it on layaway for me. ;)

[boatmangc]

It wasn't just a plug Dom,
Get it bore scoped and if it's not hurt bad a tune,
If it is hurt at all fix it now or post pictures that look like my motor last november.
Our motors window easy with boost and a bad tune.

[1stMerc]

Thought you were'nt supposed to run platinums with boost. If wrong please explain.

[burt ragio]

Lucky. Hopefully no permanent damage. A broken ring land wouldn't surprise me, but if may have gone out the exhaust and not create more problems. But if it is a broken ring land, it will probably break some more and cause additional problems in the future. Find somebody with a borescope and make sure.

Possibly detonation simply closed the plug gap, if so it's fortunate the rod didn't window the block.

Check the ring land and get a tune.... Or go ahead and get another
engine.

Sorry for lack of knowledge. What is a broken ring land ?

[Blackened300a]

Sorry for lack of knowledge. What is a broken ring land ?

http://www.lextreme.com/pistons/3uz%20015.jpg

[Black_Out]

I thought you should run copper plugs under forced induction? no?

[FordNut]

http://www.lextreme.com/pistons/3uz%20015.jpg

The picture shows the second land being broken. What frequently happens with our engines is the top land breaks and the broken piece of metal then bounces around in the combustion chamber. The top land is the section between the top of the piston and the top ring.

[FordNut]

Thought you were'nt supposed to run platinums with boost. If wrong please explain.


I thought you should run copper plugs under forced induction? no?

I run iridium plugs. I see no reason boost would dictate what kind of plugs you have to use.

[Marauderjack]

I thought you should run copper plugs under forced induction? no?

That's what I've been told and what I do......NO PLATINUMS according to blower manufacturers!!:shake:

[RF Overlord]

The Trilogy manual recommends copper plugs, although it doesn't specifically state NOT to use anything else.

Dom, what brand and part number plug were you using?

[FordNut]

Doesn't the Cobra come from the factory with platinum plugs? and a blower?

[Marauderjack]

I remember some chatter about Platinums demonstration spark "blow out" at higher boost??

Also, if you close the gap to help eliminate "blow out" the spark surfaces become cocked in relation to each other forcing to path of least resistance to become very small.....may be nothing too it and I don't know since all I've used is copper with good results!! :beer:

[LeoVampire]

Something closed the gap on that plug!!!

But I am glad I was wrong about the tranny @ least. :2thumbs: But this was not happening only while it was in drive obviously.

I just hope you don't have something else going on like the others are mentioning. :confused:

Anyways thanks for letting us know.