Vehicle squeaking under hood ??????????

[yarisfan26]

Hello,

I have a quick question for anyone who reads this! I have a 2007 Toyota Yaris and I bought it a month ago and all the sudden it has started to squeak. I noticed every time I turn the heat on something starts squeaking and when I turn it off, it stops! I don't believe its the Belt. I think it may be the water pump but I'm unsure. Also,whenever it squeaks, the rpm's go down and when it stops squeaking, the rpm's go back up. This only happens when the vehicle is cold but when it gets warm, it doesn't squeak at all. Could anyone give me some tips? I have replaced a water pump before on a Pontiac and of course its two different cars.

[CTScott]

I would check the belt. The water is always flowing, whether the heat is on or not, so most likely the belt is squeaking due to the extra current draw on the alternator from the blower fan.

Also, if you have the knob in the defrost or partial defrost position, then the AC compressor runs when you kick the heat on, so that gives you even more potential for belt squeak.

[wildcard]

you need to lube the bearings on the hampster's wheel under the hood.