HALP! Nasty engine noises, need help diagnosing.

[Rush]

2000 Mazda Protege, 1.8L, approximately 74K miles

My boyfriend drove the car to work last night and got about two blocks from his work's parking garage when the engine started making a racket. I met him in the parking garage at the end of his shift so we could have a listen to the ruckus together and try to make a diagnosis.

The engine is making a rattling/chugging noise, it literally sounds like it has magically been converted to diesel, or a tractor .. or a modded SRT-4. I stuck my head very close over the entire engine bay and the sound is definitely located right in the area of the belts/alternator, NOT in the block itself.

I had the car towed to a local shop, which I have never personally dealt with before but that has received excellent reviews online. I spoke with one of the mechanics this morning and they told me that they're always very busy with Saturday appointments, so he'd only had a couple minutes to take a listen to my car. He said based on his quick listen, he thinks it's something with the timing belt or water pump, but he'll get back to me once he's made a more though diagnosis.

The car is still on its original timing belt, water pump, alternator, etc.

Here's a link to the video of the engine noise I uploaded on YouTube:
http://www.youtube.com/watch?v=k9nLIJ_n3aQ

Any thoughts/ideas/hypotheses are greatly appreciated!!

 

[Spiced MSP]

take the valve cover off and check the tension on the timing belt. If all the accessory belts are fine, the timing belt is questionable since it's the only one not visible in the video.

 

[njintau_fsd]

My guess is its your timing belt tensioner banging against the timing cover. I'd highly recommend you change the timing belt/water pump and tensioner pulleys now cuz a noisy tensioner tells me that either the belt is stretched to the point that there's isn't enough tension or that pulley is loose. Both can lead to a jumped timing belt and your bf being stranded somewhere.

 

[Rush]

Just wanted to give an update. It was the timing belt tensioner falling apart -- good call! I replaced the whole timing belt kit (timing belt, tensioner, pulleys, etc) along with the water pump. Car is back to being its usual happy self.

Thanks for the help!!

 

[Spiced MSP]

awesome!!!