Sputtering sound comming from vents?
Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Sputtering sound coming from vents?
Since I got this car. I've noticed that whenever the blower motor is on, there is a very annoying fluttering spitting sound that comes out of the vents. Has anyone else experianced this?
Rick
Rick
Last edited by Innovator; Apr 10, 2005 at 09:05 AM.
Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
Mine has done this as well. Is it possible for trash to be inhaled by the car and it is caught on the fan?
I’ve been very disappointed in the performance of the fan when it blows (weak). When the fan speed is set at 50%, the breeze can barely be felt coming out of the vents. When the fan speed is at its maximum setting, it feels like it is operating at half its expected power.
How can you access the intake for the HVAC system to check for debris/impediments?
I’ve been very disappointed in the performance of the fan when it blows (weak). When the fan speed is set at 50%, the breeze can barely be felt coming out of the vents. When the fan speed is at its maximum setting, it feels like it is operating at half its expected power.
How can you access the intake for the HVAC system to check for debris/impediments?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The air intake for the HVAC system is O P E N without anything to prevent trash, mice, birds ect ect... 
from getting into the system. The fan motor is easily removable and in most cases you will vind trash and leaves in the motor squreal cage rotor and evaporator area. ***NOTE*** ###WARNING### Disconnect the negative battery cable prior to removing the fan motor! If you ground the fam motor housing it will turn the fan on in HIGH SPEED!!! 
Here are some pictures of the fan and HVAC ducting:
FAN MOTOR in passengers foot well!
HVAC DUCTING AND FAN
Remove the fan and clean out any trach in that cavity. The intake opening for the HVAC system is under the plastic windshield cowl below the wiper arms infront of the windshield.
BC
from getting into the system. The fan motor is easily removable and in most cases you will vind trash and leaves in the motor squreal cage rotor and evaporator area. ***NOTE*** ###WARNING### Disconnect the negative battery cable prior to removing the fan motor! If you ground the fam motor housing it will turn the fan on in HIGH SPEED!!! Here are some pictures of the fan and HVAC ducting:
FAN MOTOR in passengers foot well!
HVAC DUCTING AND FAN
Remove the fan and clean out any trach in that cavity. The intake opening for the HVAC system is under the plastic windshield cowl below the wiper arms infront of the windshield.
BC
Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
Bill,
What do you have to remove to get access to the intake? Also, would it be a good idea to put some kind of screen over the intake area to prevent additional large debris from getting inside?
Thanks for the great pictures!!
What do you have to remove to get access to the intake? Also, would it be a good idea to put some kind of screen over the intake area to prevent additional large debris from getting inside?
Thanks for the great pictures!!
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You need to remove the wiper arms. There is a cap plastic on the arms that get pried off. Under it there will be a 13 mm nut. Remove that, lift off the arms (dont get the left and right arms mixed up!). Next there are a bunch of plastic push pin rivits. Pull the center pin up and the rivits will pull out. Then you can pull the plastic windshield cowl up. The HVAC air intake will be in that void on the passengers side.
You can frabricate and install a coarse stainless steel wire mesh screen if you desire.
While your in that area, make sure that your cowl drains are clean!! If they are clogged up, your wiper motor will short out and burn up.
Here are pictures of the drains. With the cowl off you can see if there is water backed up in the wiper motor well.
You can reach into this area and access the drain tubes with yiur hand. If they are HARD they are full of nasty gook and need to be milked out:
Here is what was in my drains!
You can frabricate and install a coarse stainless steel wire mesh screen if you desire.
While your in that area, make sure that your cowl drains are clean!! If they are clogged up, your wiper motor will short out and burn up.
Here are pictures of the drains. With the cowl off you can see if there is water backed up in the wiper motor well.
You can reach into this area and access the drain tubes with yiur hand. If they are HARD they are full of nasty gook and need to be milked out:
Here is what was in my drains!
Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
Bill,
I removed the cowl plastic piece, but now there is another plastic piece underneath that appears to be riveted to the car (cannot remove it). This is on the passenger side where you said the HVAC intake is.
How do I access the intake from here?
Thanks!
I removed the cowl plastic piece, but now there is another plastic piece underneath that appears to be riveted to the car (cannot remove it). This is on the passenger side where you said the HVAC intake is.
How do I access the intake from here?
Thanks!
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Normaly you can see trash and leaves in that area. The plastic shroud can not be removed easily. I recommend that you remove the fan motor. Everything is accassable from there. You can put your hand up into the evap coil area, check the fan motor for trash and clean out the duct.
BC
BC
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Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
Thanks Bill!
I plan on getting a vacuum hose in there tomorrow (can't wake our baby this late at night) to see if I get any debris out. It "looks" clear from my viewpoint and there was very little trash under the cowl so everything is probably fine.
Thanks,
I plan on getting a vacuum hose in there tomorrow (can't wake our baby this late at night) to see if I get any debris out. It "looks" clear from my viewpoint and there was very little trash under the cowl so everything is probably fine.
Thanks,
Melting Slicks
Joined: Jul 2004
Posts: 2,567
Likes: 1
From: Edmond, OK...One of the first rules of online forums: If you don't like what is said but can't refute it, attack the poster.
mine has made that noise since new. it only makes it when the air is coming out of the vents. doesnt make the noise from the def or the heater vents. I took it in to the dealership and they said it was normal. had something to do with the routing of the vent ducts in proximity with the evap core.....or some kind of bs like that. lol
jeff
jeff
Thread Starter
Instructor
Joined: Mar 2005
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Originally Posted by JeffC5
mine has made that noise since new. it only makes it when the air is coming out of the vents. doesnt make the noise from the def or the heater vents. I took it in to the dealership and they said it was normal. had something to do with the routing of the vent ducts in proximity with the evap core.....or some kind of bs like that. lol
jeff
jeff
Advanced
Joined: Aug 2003
Posts: 74
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From: North Myrtle Beach SC
Mine (02 Vert) has had the same noise (a flapping sound like that black plastic vent wrap would make) since new but the only time I tend to hear it is when the ambient temp is cold. I took it back to the dealer when it was six months old and they said it was the blower motor - replaced under warranty. I don't normally drive the car in the winter so I thought the problem was fixed but I had to use it this past winter a few times and I found the noise was back. I did a little experimenting and this is what I found:
The noise can only be heard from the defroster vent when -
1. The ambient temp must be blow 40 degrees.
2. The car is first started in the morning.
3. The car is not moving.
I can force the noise by -
1. Turning on the windshield defroster.
2. Turning up the fan speed to max.
3. Turning up the cabin temp to max (90 degrees for the Auto HVAC system).
I called the dealer again to schedule a return appointment - I'll keep in mind to mention the debris theory and report back if there is anything new to look for.
The noise can only be heard from the defroster vent when -
1. The ambient temp must be blow 40 degrees.
2. The car is first started in the morning.
3. The car is not moving.
I can force the noise by -
1. Turning on the windshield defroster.
2. Turning up the fan speed to max.
3. Turning up the cabin temp to max (90 degrees for the Auto HVAC system).
I called the dealer again to schedule a return appointment - I'll keep in mind to mention the debris theory and report back if there is anything new to look for.
