HVAC fan noise tic,tic,tic

I recently heard a dash rattle (or so I thought!) that drove me nuts. It was barely audiable with the radio on at first, but it was constant speed, regardless of car velocity or road conditions.

 

 

Then I turned off the radio and manually changed the A/C fan speed on the climate control to realize that this high-speed ticking not only got louder, but also faster as the fan speed increased. This means that the HVAC blower must somehow be involved (when off there is no noise). Any ideas where to look or how to get there? I don't have the air filtration system, mostly b/c I don't have the overpriced $80 trapdoor install and didn't want to pull 1/2 the damn car apart to get to the thing on a 7,000 mile basis.

 

Got any suggestions or anyone with a similar past/present tictictic problem?

 

Mike

Uh oh. That sounds like the dreaded clogged AC line. You might want to check your passenger side floor for water/moisture. The ductwork fills with water from the clogged AC line and when the water reaches a certain level the fan spins and hits the water. This sound happened to me and it turned out to be the AC line clogged.

 

Of course it could be totally something else but that's my guess.

hmm... on a brand new car? sounds scary... details details details!

http://legacygt.com/forums/showthread.php?t=18050&highlight=water+passenger

Well... I started digging around there to see if it was wet. Nothing apeared wet, so I pulled the plastic piece off below the glove box -- dry. Turn on the HVAC fan and suddenly the noise is gone, when I clearly heard it a few minutes earlier! Must have been something lose. As a plus, I noticed a small puddle under the car, so it must not be a clogged line. Yay! I can sleep in tomrrow instead of driving an hour to my 1/2-ass dealership!

 

Thanks for the advice and link!

 

Mike

could have been a leaf or small twig or something that got sucked in

i had this same problem start last night. this is not related to the clogged AC line or water in the passenger foot area. it sounds more like a leaf or wire hitting the fan, like a tic tic ticking that speeds up/slows down with the fan speed.

 

today the problem persisted so i put the fan on the HIGH setting and cycled through all of the venting modes. when i turned the fan back to LOW the ticking had stopped.

 

this is just an FYI for anyone else who experiences this problem. not sure what it was but its gone now and i'm happy. i think it is the same issue that mlloydlgt had in the original post.

could have been a leaf or small twig or something that got sucked in

That's my vote, too.

I went through this too. Having the fan on high and cycling modes caused whatever it was to blow away from the fan. I suppose if I added the cabin filtration this would get stuck in the filter instead?

My wife just noticed a similar sound today...I checked it out and there is a ticking type of sound coming from the area directly behind the glove box. it's only noticeable when the fan is set on low...I cycled the fan to high-low several times but the sound is still there...looks like I have some digging around to do.

I just today had my HVAC fan make noise only on the higher settings it sounds like the fan is working hard but not blowing any air really. it doesnt matter what mode or is the ac is on or not. the fan makes a deep tone like its struggling to push any air. Any suggestions on what this might be?

I had similar thing with my old car. opening up blower revealed some leafs and tree seeds being stuck in teeth of blower, making clicking sound and restricting blower rotation and airflow.

i had this start happening to me last night... i am going to check if there is anything caught up in the fan....but i am not experiencing any lack in air flow like you described Neisy.... if i put in a cabin air filter will it defeat this problem in the future???

I had my HVAC fan replaced under warranty 2 weeks ago. Made noises beginning in early fall - the ball bearings were worn out. There was no significant decrease in air flow - I also took it out and after I removed a twig, the noise augmented.

Ok this is weird. A noise from the blower fan started up today. Tick, tick tick - and faster as the fan was set higher. Then this afternoon, I turned the defrost button "off" (with the fan still blowing) and the noise stopped. Hit the defrost "on" and the noise was still gone - no more noise - great right? or is it the beginning of something going bad?

 

If something was getting into the blower fan, how could turning the ac/defrost on/off dislodge anything if the fan was constantly on

the blower door moved and dislodged whatever it was