Enginge bay rattle on passenger side - advice

[aliasofmike]

I've been doing research regarding a rattle that has presented in my girlfriend's 2007 Toyota yaris (1NZ-FE). The car has 104k miles, and the rattling was noticed just recently. It appears to be getting worse.

It seemed like the most common problem was with the water pump. I've taken a look at it, and I don't notice any pink residue, and in general the pulley seems in good repair. I wasn't able to get a great look at it.

The other possibility I am considering is that the noise is coming from the A/C assembly. I found less information on diagnosing this, and I'm not sure where too look. The A/C still works and the noise doesn't increase when the A/C on, fwiw.

The noise is apparent while idling, and increases with RPMs to a point.

It is very hot weather here, and were planning on taking a day trip tomorrow. If it is the water pump, I'm concerned that this would be a gamble/bad idea.

Any advice or questions for me to follow up on, much appreciated.

[Z00KA]

See if the rattle changes or goes away when you cycle on and off the A/C. At least you can eliminate it as a cause if it doesn't change.

[aliasofmike]

Cycling on or off the A/C does not change the noise. Same goes with the fan.

[CTScott]

You could loosen the belt and spin the compressor and water pump by hand to see if either feels like the bearings are shot.

[why?]

does the car have an in cabin air filter? It would be located right behind the passenger glove box. If not, stuff can get in there and cause noises.

More info is needed. Does it rattle if you hit the gas with the car out of gear?

[aliasofmike]

Thanks for the responses guys.

I'm not too car savy, but it seems to be distinctly coming from the area of the belt driven components on that side of the motor.

Interestingly, we took the car for a 45 minute highway drive, and the noise became intermittent and then stopped. It changed over the course of the drive, becoming clearly a function of RPMs, before cutting out. Before this happened, yes it did rattle with the car out of gear.

[JeanaVilee]

Thanks your share!I need these things!

[c-dub]

sounds like the same issue in my girls car. going to try and take a good look today.

[c-dub]

did this today. Pulled the accessory belt off and the noise went away. Put it back on and it was back. Pulled out a stethoscope and tried to listen for anything out of the ordinary on the a/c, alt and water pump. Think I can hear the noise coming from the water pump. Every thing else sounded normal, but I can hear the rattle when I put the scope on the water pump near the pulley just not as loud. Any ideas?:iono:

[c-dub]

i'm gonna say change the water pump, did mine today and fixed the issue.

if it sounds like this than its the pump...
http://www.youtube.com/watch?v=M_ggV2MSxTM

[victorddr]

I would say before you change anything. Double check your accessory belt condition and tension first, as your car has ran 104k mile. The belt itself could possibly loosen up or crack occurs between the groove. you may save yourself some $$ before replace any parts by tighten a bolt...

[wsladaritz]

c-dub, just want to say thanks for posting that vid. U just saved me some trouble :) That sounds EXACTLY like mine.