CristalCleanCivic 97 EX

Its a 97 civic ex with just a catback exhaust system w/ 2.25 piping and an AEM cai w/ 56k miles. AT IDLE, I first noticed the increased vibration when parts of my front, center console started to vibrate out of place (like the plastic panel that holds the hazard light button, and especially the plastic panel to the left of the AC temp sliding controls.. which if I put pressure to it w/ my thumb mutes the noise.. which is beside the main problem of the vibration)
All of the vibration starts when I turn my AC on 123or4, it doesn't matter. The most recent changes done to my car has been finally changing my spark plugs to NGK's G Power plugs, ES (shifter) stabilizer bushings, drained-refilled transmission fluid, flushed-replaced brake and clutch fluid, and flushed-replaced engine coolant.
Besides the vibration noise behind the front center console, I also notice my shifter vibrates 2-3x the normal rate. All this vibration seems to stop as soon as I release my clutch and get into gear! Also , at idle w/ AC ON, I noticed under the hood that my engine seems to vibrate violently and in the rear of the car, my muffler also shakes violently.. Not sure if this stops as I get into gear.
I reallly want my smooth AC running engine back.

I hope I can rule out the motor mounts because there is less vibration as I get into gear.. the shift **** stobs vibrating and the fr center console stops tmake noise.

i took it to a small hi performance shop and he said it was normal vibration he sees in a lot of Hondas,..... but I know it's NOT because it just started recently and has been increasing in vibration for the last two months... and it is irritating the hell out of me and I've been looking at other civics' perf mufflers and they all seem quite stationary w/ minimal to no vibration.. anyway, he said that when his car increases a little at idle, he normally knows that his spark plugs are going bad and he aslo recommended changing my caps and rotor.

What could the problem be?
thanks fellas




Modified by CristalCleanCivic 97 EX at 7:17 PM 8/1/2003

Mr. Choi

well an engine usually starts to vibrate harder with age, but your car only has 56k on it. i have a 2000 civic
with 51K and very smooth. after reading this twice the only thing i can tell you is check the idle speed.
does the idle drop when you turn the AC on? if yes then check the idle control valve or whatever
our hondas come with. do you have those after market engine mounts? cause those thing doesnt
absorb vibrations like stock rubbers do.

hope i helped and others add on.

CristalCleanCivic 97 EX

No, I think the idle speed alright..it stays betweent 700-900 at idle....with occasional drops under that, but nothing constantly happening.
I also had my alternator belt tightened RECENTLY because I had some squeaking coming from it.

And I have stock motor mounts.
Thanks


Modified by CristalCleanCivic 97 EX at 2:38 AM 8/2/2003

CristalCleanCivic 97 EX

Mr. Choi

no idea man, maybe jus old age.

Yougod

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CristalCleanCivic 97 EX &raquo;</TD></TR><TR><TD CLASS="quote"> I hope I can rule out the motor mounts because there is less vibration as I get into gear.. the shift **** stobs vibrating and the fr center console stops tmake noise.
</TD></TR></TABLE>

Rule out the motor mounts by using a big bar (prybar w/ handle works) to shift engine position. If the vibration changes while moving the engine around then it IS the mounts. Depending on which mount you are moving the engine around at... that mount would be bad.

This is more of a problem with older Accords with the actuated rear mount.

Mohudsolo

The idle should jump up 2-300 with the AC on versus normal idle. If not, check the idle circuit. I would suspect something is touching the body, like the exhaust, or the shifter is not mounted right. Something is giving a direct connection between the body and motor. Putting it under load from power rotates it away from whatever is touching. At idle try putting a jack under the engine and lift slightly. If it goes away, check the mounts and make sure everything attached to the motor is run correctly. Some Hondas have a fluid filled rear mount that can leak and stop working. Avoid any shop that tells you Hondas vibrate. Check any roadtest, they always fall all over themselves trying to say just how smooth the latest Honda is.

CristalCleanCivic 97 EX

I think I may have solved the problem of why my muffler is shaking so much. The way my cat-back piping was installed may be the reason. I notice that the piping starts to vibrate right after the cat.. and increases in vibration until you get to the muffler where it shakes the most! The original connection of the a-pipe to the cat seems to have (2) some type of spring looking peices attached along w/ the bolts holding the flanges together. Could this be dampening the vibrations? Then when I look at the connection between the cat and the rest of the piping, they are just bolted together! SHOULD THERE BE THOSE THOSE SPRINGS, ALSO?

I'm going to try your suggestion of elevating my engine slightly to try to rule out the engine mounts, especially the rear mount.

Mohudsolo

My GSR uses the spring mounts(2) from the header to the cat and normal bolts(3) from the cat to the catback. The joint in front of the rear muffler also has the sprung bolt mounts. Check along the whole exhaust, a hanger may be broken or missing or it could be touching bodywork somwhere.

CristalCleanCivic 97 EX

I've tried elevating my engine w/ my jack beneath the oil pan, & my shifter and muffler seem to reduce in vibration slightly... It's hard to tell whether the shirt I placed between the jack and oil pan just absorbs the vibration a little better or if the engine mount is actually bad. I remember tearing my oil filled driver's side engine mount after I had launched too high, and before I replaced it, the vibration level didn't increase by much over the next 2-3 months! So, I'm still not really positive or should that be a positive sign? Just a reminder, the vibrations have been increasing slowly over the last four to six months.

Even if I do find out it is the motor mounts, Is there a way to figure out which has gone bad?
Getting a little closer to solving the problem.. so i really appreciate the replies.

Yougod

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Yougod &raquo;</TD></TR><TR><TD CLASS="quote">

Rule out the motor mounts by using a big bar (prybar w/ handle works) to shift engine position. If the vibration changes while moving the engine around then it IS the mounts. Depending on which mount you are moving the engine around at... that mount would be bad.

This is more of a problem with older Accords with the actuated rear mount.</TD></TR></TABLE>

Whichever mount you have the prybar at when the noise changes is the bad mount.

CristalCleanCivic 97 EX

Yup, I tried elevating the motor again and the vibration decreased to the point where my fr ctr console didn't make vibrating noises. There is still vibration of course, but it lowered it by half. Will a new mount decrease the vibration as much as it has by elevating it w/ the jack? or is it a possibility that its a combination of all my mounts, from the time of original purchase, slowly aging and going bad?
How many mounts are there on my civic? I counted FOUR...I can exclude the driver's upper mount(close to the dipstick) because its new and there isn't any oil leaking from it. Also, there are two connected to the transmission(on the passenger side) and one I can hardly see or probably get to in the lower rear of the engine.
Is there another one?
And I'm thinking, you stabilize the pry bar on the mounting brackets to slighty move around the actual mount?

Almost there!

CristalCleanCivic 97 EX

Yougod

If you replace the correct mount/mounts it should totally eliminate the vibration. I doubt you will have to replace all the mounts.
I believe on your particular car there are 4 mounts that can be the basis of this problem. If you find out that neither side mount is causing a vibration check the front one with a bar and visually. If that one is ok then chances are it's the rear one. Those are the ones that usually cause vibration during A/C.
You'd probably have to get someone to sit in the car when it's jacked up and get under there and wedge a prybar in there to move it around. Just remember, you're not looking for the vibration to go away. You're looking for a CHANGE in vibration noise.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CristalCleanCivic 97 EX &raquo;</TD></TR><TR><TD CLASS="quote"> And I'm thinking, you stabilize the pry bar on the mounting brackets to slighty move around the actual mount?
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