GenVibe - Community for Pontiac Vibe Enthusiasts

Hello all, this is my first post on this site but Ive been an avid reader of post for some time. I am the proud owner of an 08' base vibe this vehicle has been incredibly reliable for a vehicle that is fixing to turn over 200k. Ive been on a crusade to start fixing it up to give it new life for another 200k. For the past two months Ive noticed a metallic grinding noise coming from the pulley side of the engine while running. I was concerned it may be the timing chain so I opened up the oil cap while running to see if the noise was internal. Thankfully I couldn't hear the noise internally but, it defiantly seems to be coming from one of the pulleys. After reading post on this site Ive determined the probable culprit is the Tensioner pulley. I purchased a replacement on amazon along with a new serpentine belt since I will have to take it off I figured I'd replace that while it was off. I am just wanting to check with you Vibe/matrix veterans to make sure I'm not overlooking any potential causes. I saw a post that described the sound perfectly "marbles rolling around in a plastic cup" that is about as close a description as I can get. Any input from any of you fellow owners is appreciated.

JP

Other possibility is a bad water pump, makes a growling sound when it goes bad.

Be prepared to jack up the engine a little bit to get the serpentine tensioner bolt out. Just have to unbolt the top engine mount and use a piece of wood between the oil pan and Jack.

Thank you for your reply, wouldn't there be some sort of leaking from the pump itself. I haven't noticed any coolant loss or fluxuation of engine temp ....yet :-/

Not necessarily, the impeller runs on bearings that can go bad.
I replaced a bad one that made an awful growling noise and only showed a minimal amount of leaking.

I vote for a water pump also. Buy a cheap mechanics stethoscope. I had that horrible sound at around 100k miles, I originally thought it was the alternator. I replaced that since it was the easiest, but it wasn't. Thankfully the store took it back. I replaced the water pump and the sound went away. I'm at 255k miles now and no problems.

Your timing chain tensioner could also be failing to provide sufficient tension. It would not be great to have it slip off a tooth (which could damage the chain or a timing sprocket), but the 1ZZ-FE engine is supposed to be non-interference (barring more aggressive cams) so it might not be as catastrophic as it could be. The tensioner is only $20-30 and you'll only need a flatblade screwdriver, a 17 mm socket, and a 10 mm deep socket to replace it. I recommend using a sealant or RTV gasket around the o-ring, as sometimes the o-ring can be faulty and let a ton of oil escape pretty rapidly. I did this when I replaced the o-ring on mine; it didn't make removing the tensioner any more difficult when it started slacking off a couple of years later.

You can try removing your serpentine belt and turning each pulley by hand. It's easiest to put the belt back on the alternator when you are reinstalling it; usually it's better to put the belt on a smooth pulley, but it's a lot easier to slip it onto the alternator on these engines.

Do the timing chain tensioners routinely wear out? Perhaps I should go ahead and replace it since I am doing the o-ring anyway? I hate to throw $30 at replacing something that ISN'T bad. On the other hand, I'd rather not pull it, find it needs replacing and have to put it back until I get another one..

EDIT: I looked on Amazon and found it for $23.81 with tax, and Prime shipping, so I went ahead and ordered it for good measure. $24 is cheaper than having to take it to a mechanic for a loose timing chain. I can get away with doing small stuff in the parking lot here where I live, like the tensioner, but a timing chain would be waaaay too much.

Amazon nags that it doesn't fit a Vibe of course
http://www.amazon.com/gp/product/B00GJH ... ge_o00_s00

The GM/AC Delco one on Amazon is over $40.
http://www.amazon.com/ACDelco-88969018- ... iac%3Avibe

Just a tip to add , if your replacing the belt tensioner yourself make sure that the pivot/mounting bolt isn't over-torqued when its reinstalled and ensure you put an anti seize lubricant on it. Mine was over-torqued by accident during an alternator replacement (or so we thing ) and the bolt eventually sheared off in the engine a couple weeks later while we were driving. cost me over $1000 to have it removed. This has happened to a few people with the 1zz engine so I've read on the web.