Timing Belt Wear -What are the Symptoms?

[1gasenvy1]

I have a 1999 1.0 cylinder Chevy Metro with 183k. The engine has a slight vibration at speed in 4 gear above 30mph. It sounds like something is rubbing. I had a mechanic test the water pump, he says it has plenty of pressure so I don't think that's the problem. I inspected the bolts that secure the timing belt cover and they don't appear to have been wrenched. From what I have determined the belt and pully should have been replaced at 60k. Is this the sign/sound of a bad timing belt.
In addition I just recently replaced the injector. Could this be the cause as well?
Or, one other thought, could it be the throwout bearing on the tranny?

I don't want to start tearing down the front on the engine without knowing what the source of this anoying vibration is.

Can anyone help?

Metro's Forever
Gasenvy

[Crvett69]

it could also be a cv axle. if it was belt it should do it in all gears at the same RPM

[Woodie83]

There are no symptoms of timing belt trouble. It works perfectly until it is stone dead. It is a good idea to change it though, they do break and leave you stranded. While you're in there, replace the timing belt tensioner and water pump.

Most vibrations are suspension or wheel and tire related.

[Colt1911]

yeah the timing belt just break suddenly, you can take the top two bolts off the cover and peek through using a flashlight, and inspect it for cracks. Chances are good its past its prime.

To narrow your search for the vibration, get up to speed, and push in the clutch. If the vibration goes away instantly, you probably have an issue with your clutch assembly. If not its probably a tire, or suspension issue.

I have seen a really weak shock cause vibration a certain speeds, and suspension bushings aswell (on different cars). I kind of think I would check the clutch engagement. I have a auto model, so I'm not familiar with metro clutch assemblies, some cars have slf adjusting clutches.