"Hissing" on Driver's Side (1 Viewer)

[Beams37]

I'm sure I've heard it before, but didn't notice because the drive's were so short. However, the hissing became much more noticeable on the 2 hour drive from the beach today. In my wife's 2008, it sounds like there is an intermittent "hissing" coming from the driver's side door area. Anyone know what this is? Ideas? Thoughts?

Thanks.

 

[JohnJB]

If hissing is from lower dash on driver side, it’s possible that it’s the AC expansion valve due to low Freon. Easiest way to test, drive with AC on and listen for noise. Once you regularly hear it, turn off AC and see if this remedies noise. If so, you might need to have the system properly evacuated and refilled.

If not related to use of AC, disregard.

 

[Markuson]

I'm sure I've heard it before, but didn't notice because the drive's were so short. However, the hissing became much more noticeable on the 2 hour drive from the beach today. In my wife's 2008, it sounds like there is an intermittent "hissing" coming from the driver's side door area. Anyone know what this is? Ideas? Thoughts?

Thanks.

Don’t know, but one possibility:
If it’s a smallish noise...it could be a clogged temperature gauge hole. Most have never paid much attention, but there is a tiny, slotted hole in the lower dash, down near driver’s legs that actually sucks in air to measure its temperature. Pretty sure it is the sensor that controls that corner of the 4-zone temp interior temps.

There might be something caught in there, like a piece of a wrapper, or something that is creating noise.

This spot...to the right of the steering wheel...has tubing behind it and a sensor at the opening. From the looks of mine, looks like mine is pretty clogged with dust as well...

 

[Beams37]

Don’t know, but one possibility:
If it’s a smallish noise...it could be a clogged temperature gauge hole. Most have never paid much attention, but there is a tiny, slotted hole in the lower dash, down near driver’s legs that actually sucks in air to measure its temperature. Pretty sure it is the sensor that controls that corner of the 4-zone temp interior temps.

There might be something caught in there, like a piece of a wrapper, or something that is creating noise.

This spot...to the right of the steering wheel...has tubing behind it and a sensor at the opening. From the looks of mine, looks like mine is pretty clogged with dust as well...
View attachment 2017505

Going to give that a shot.

 

[Beams37]

Don’t know, but one possibility:
If it’s a smallish noise...it could be a clogged temperature gauge hole. Most have never paid much attention, but there is a tiny, slotted hole in the lower dash, down near driver’s legs that actually sucks in air to measure its temperature. Pretty sure it is the sensor that controls that corner of the 4-zone temp interior temps.

There might be something caught in there, like a piece of a wrapper, or something that is creating noise.

This spot...to the right of the steering wheel...has tubing behind it and a sensor at the opening. From the looks of mine, looks like mine is pretty clogged with dust as well...
View attachment 2017505

Not it. I hear it more towards the driver's door/window/tweeter. Any other ideas?

 

[Beams37]

I did some listening and looking. There is what appears to be a line for the AC system running around in front of the dash (near the brake booster). I assume the system is a vacuum? Could I be a hearing a leak? I was getting the sound only when the system was on.

Thoughts??

 

[JohnJB]

Thoughts??

“Per my last email”

The system is likely slightly low on refrigerant. I had this same issue and having it properly topped off has cured the hissing blues for the meantime. The hiss is a symptom of the issue, not a leak itself. Another member with a 2015 had the same issue. Of course they’ll dye the system as well in case you need to chase a leak later. Do not just top it off with a DIY kit.

 

[Markuson]

I did some listening and looking. There is what appears to be a line for the AC system running around in front of the dash (near the brake booster). I assume the system is a vacuum? Could I be a hearing a leak? I was getting the sound only when the system was on.

Thoughts??

If not getting a result...try posting a video of it with sound (youtube).

Another little sound origin trick that sometimes helps is using your phone video another way:

-Shoot a continuous video and slowly move your phone (and it’s several microphones) around slowly from area to area. While your ears might not pick up the difference from where your head/ears can position, your ohone’s Microphones can register loud/quiet with close proximity. So...shoot video...then watch it carefully and listen for volume changes during playback, noting where it is loudest.

**Use headphones for playback since your phone speaker might not be able to reproduce it as well.

 

[Beams37]

If not getting a result...try posting a video of it with sound (youtube).

Another little sound origin trick that sometimes helps is using your phone video another way:

-Shoot a continuous video and slowly move your phone (and it’s several microphones) around slowly from area to area. While your ears might not pick up the difference from where your head/ears can position, your ohone’s Microphones can register loud/quiet with close proximity. So...shoot video...then watch it carefully and listen for volume changes during playback, noting where it is loudest.

**Use headphones for playback since your phone speaker might not be able to reproduce it as well.

Dude ... I took like 10 videos and none of them would pinpoint the sound. I was mad and sweaty when I decided to call it.

 

[Beams37]

“Per my last email”

The system is likely slightly low on refrigerant. I had this same issue and having it properly topped off has cured the hissing blues for the meantime. The hiss is a symptom of the issue, not a leak itself. Another member with a 2015 had the same issue. Of course they’ll dye the system as well in case you need to chase a leak later. Do not just top it off with a DIY kit.

Any reason I wouldn't use a DIY kit? Never used one, but seems like it would do the same thing as a professional system.

 

[Markuson]

Any reason I wouldn't use a DIY kit? Never used one, but seems like it would do the same thing as a professional system.

I think he meant that it won’t identify a leak if you just add refrigerant.

 

[Beams37]

I think he meant that it won’t identify a leak if you just add refrigerant.

Aaaaaahhhhh. Thanks.

 

[Markuson]

Dude ... I took like 10 videos and none of them would pinpoint the sound. I was mad and sweaty when I decided to call it.

Ya, doesn’t always work. Sometimes the audible sound isn’t direct...transferred through other surfaces etc. Oh well. I’ve used the trick to figure out sources of various other noises

 

[JohnJB]

Any reason I wouldn't use a DIY kit? Never used one, but seems like it would do the same thing as a professional system.

Couple reasons from my limited knowledge base. One, the system is clearly sensitive to small variations in charge. I talked to my tech and he said if it didn’t hiss, he would have never serviced the system as it was just at bare minimum of recommended charge. If you’re experiencing what I did, I bet your air is plenty cold, it just hisses due to being slightly under charged. I wouldn’t trust the gauge on a DIY kit compared to a professional machine with a knowledgeable operator. Two, most of the DIY kits contain sealants which can gunk up the system, which can lead to costly and needless repairs later.

I shamelessly went to the dealer for this. The noise was just annoying overtime even though I had no complaints related to air temperature performance.

 

[Beams37]

Couple reasons from my limited knowledge base. One, the system is clearly sensitive to small variations in charge. I talked to my tech and he said if it didn’t hiss, he would have never serviced the system as it was just at bare minimum of recommended charge. If you’re experiencing what I did, I bet your air is plenty cold, it just hisses due to being slightly under charged. I wouldn’t trust the gauge on a DIY kit compared to a professional machine with a knowledgeable operator. Two, most of the DIY kits contain sealants which can gunk up the system, which can lead to costly and needless repairs later.

I shamelessly went to the dealer for this. The noise was just annoying overtime even though I had no complaints related to air temperature performance.

Great intel.

 

[Markuson]

Great intel.

One of the best things I ever inadvertently caused...was a huge leak of refrigerant while digging through my Coolbox fan replacement (nightmare of a mess getting access).

The upshot was...since the system was fouled by condensation/water from the opening and super-cooling...I had to have Toyota fully evacuate the system...and replace not only refrigerant, but also oil that is also in the system.

The result of this was a remarkably more powerful cooling ability. Even though I had no complaints about the strength of cooling I 108 degree Moab heat...I was seriously blown away by the improvement. Was not terribly expensive, either.

Moral of the story is... for older 200’s...it might be worth a complete evacuation rather than a simple recharge—assuming any leak has been remedied.

Whether this fixes your annoying noise...no idea...but I highly recommend the full system evac & cooling system oil + refrigerant. My 2008 practically spits ice-cubes now!

 

[bloc]

Any reason I wouldn't use a DIY kit? Never used one, but seems like it would do the same thing as a professional system.

Good reasons, actually. The best way to charge the system is start from zero and add the specified mass of refrigerant. If you can't do that, like when topping up, the relationship between low and high side pressures compared to ambient and vent temp is key to getting the charge amount correct.

Using the DIY bottle with hose and invariably cheap gauge only gives you one very small part of all the info you need to do it right. I've done good work with a set of low and high gauges and a thermometer... but I had to pay $125 or so for the set.

 

[EverywhereBear]

The system is likely slightly low on refrigerant. I had this same issue and having it properly topped off has cured the hissing blues for the meantime. The hiss is a symptom of the issue, not a leak itself. Another member with a 2015 had the same issue. Of course they’ll dye the system as well in case you need to chase a leak later. Do not just top it off with a DIY kit.

This was the case for me as well. The hissing was due to low refrigerant - I have a tiny leak in the rear unit. Once they topped it off the hissing went away.

 

[TacomaLC]

Not sure if you've checked this: Does she have ventilated seats? my seats are ventilated and in auto they turn on and off and it is a hissing sound on the highest seat fan setting.

 

[gettnthar]

My ‘09 LC started making this noise a couple years ago. Never had a problem with the temperature, so never looked into it. Figured just like “cruiser lean” it’s one of those benign quirks and features...