For quite some time now there has been an engine vibration in my car... it only happens 90-95% of the time though, the other 5% of the time it's perfect like it should be.

Does anyone know what can cause this? Can ignition timing be an issue? Is timing suppossed to be at 0deg at 1000RPM?

 

I think we'll need a bit more description, does it only happen while moving? while stopped? both? Does it only do it when warm, when cold, or both? How is the idle, does it sound constant? Is your tach reporting anything wierd, or is a solid idle/RPM? And to make sure it's the engine, have you shut down the engine while moving (fair warning: this is potentially dangerous, make sure you're on a clear road with no obstructions and/or other people on the road)?

Just for the record, I am likely not going to be able to help you out, but I figured I'd get the information that the more informed members will need to help you diagnose it

 

ok.

it IS the engine, must be. MUST. Can't be anything else. Engine off with car moving = no vibration. Engine on with car not moving = vibration.

idle is screwed, but not related to this problem. I haven't figured out the idle issues yet (sometimes idles perfectly other times won't idle, etc...)

sometimes its PERFECTLY smooth... other times it'll rattle your teeth out and you can't see out the rear view mirror for the vibration.

Wonko: NICE paint. I love the color.

 

I don't think it can be air or fuel related, either.

if I go like 120km/h in 4th gear and shut the ignition off but leave the engine spin with the wheels, it will still vibrate, but not every time.

in neutral at a full stop it will vibrate.

 

tranny mount i think.

 

strange.. my car vibrated so much b4 my tps adjust that the shifter would fly around....

it happens while moving and at idle? if its only idling its probably your.. idle! if it happens while moving it could easily be a motor mount.. got any tq dampeners? check the mounts.. you motor vibrates alot when you drive, the mounts usually pick that up. the only other thing that would cause that would be low compression on a single rotor causing lopsided combustion.

 

check this out, it should help, http://www.mazdatrix.com/g2.htm

 

Thanks Terrh!

Here's my guess: Either Engine mounts, tranny mounts, or your driveshaft. I know I have some minor vibration that's getting worse, and it'll vary where it's at from 40-90 mph. I'm 99% certain that's my ball joints, because there's a little bit of play if you go up and pull on the front wheels, but mine will do it reguardless of whether the engine is on or not, so I know mine isn't a mount problem, and I just got a new driveshaft. So while I'm in there, i'm going to replace the wheel bearings, too.

But i'd start with the engine/tranny mounts, they're cheap. Then i'd look into a new driveshaft, or U-joints if you have an aftermarket driveshaft?

 

I have NO idea if my tranny mount is OK.

Engine mounts are PERRRRFECT.

(brand new, couldn't be better). it did this before I replaced them too.

Stuff I've replaced (and it still does it: fan (converted to electric), airpump (removed) removed p/s and a/c belts (to see if one of them was the problem), water pump, transmission, engine mounts. TPS (I think I need to set it again though, it seems like it cuts fuel before 0% throttle). I'm sure there's more, too.

 

Oh, sure, already try the obvious stuff before posting a question.. you're one of the ones who actually searches and attempts to fix your own problems... I see how YOU are....




You should be able to feel the source of the vibration, if you open the hood and start feeling around in the bay (i'd do this when the engine is cold....), to get a more exact idea of where it's coming from.. if the enitre engine block is jerking around, then my guess would be either a bearing or a fuel/spark problem.. . but that's going to be out of my league...

 

what does it sound like? misfire maybe? I would try and smooth your idle out, it could be a problem that is compounding itself.

 

Uh.. Do you have a strut bar that is very near/touching the alternator? I recall some saying that their strut bars didn't fit so well and the car vibrated a lot from the strut coming into contact with the alternator...