I test drove a 99 GS400 this weekend and there was a humming noisie inside the cabin with the a/c on. The noise increased when I accelerated. The owner told me that it was coming from he cabin filter cause he used the wrong size filter and thats where the noise is coming from. Is that the case or what else it could be?

 

Check the ac cabin filter to see if its true.
https://www.clublexus.com/forums/gs-...ts-of-pix.html

 

That is what I was planning on doing when I go get it tomorrow.

 

I don't think the noise is due to the filter...

 

I think its the a/c blower motor.

 

Or one of the servos.

 

IF he used a way smaller filter, yes its possible u would have some noise....but this doesnt sound right no matter what possibility i try and make it. do one of 2 things....GO BUY THE RIGHT FILTER and see if you have the same noise OR make us a video so we can hear it. any issues going on with the car?

 

Im set to purchase the car from a private seller tomorrow. I test his theory with the correct cabin filter. If the noise continues Im unsure if I will get the car but I am getting it for a good price which the noise is probably why.

 

make a video of the noise when u test drive it.....let us help you think it over


the reason i dont think its a servo is cause the noise shouldnt increase as you accelerate but with the blower motor its possible as more air can get in there.say for example, if he doesnt have a filter in there at all, the noise can increase with more speed thus causing a sound although if he has the wrong size it shouldnt increase the noise unless its way to small for it.

i wont know for sure without being there or hearing it....

 

it could be you subconsciously humming while your driving.......