Vacuum leak
Thread Starter
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Joined: Apr 2008
Posts: 112
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From: Massachusetts
'02 C320 Wagon
Vacuum leak
Alright - I'm pretty sure I have a vacuum leak somewhere in my ventilation system. When I'm cruising down the road and have the ventilation set to blow through the dash vents, it takes just a tiny bit of throttle (less manifold vacuum) to make the setting change to the default floor/defrost setting, and it takes a good 30 seconds for vacuum to build back up to the point where the vents correct themselves. From my experience in the past with other vehicles, this is a pretty textbook situation.
My question is: are there any areas that I ought to be checking first? Are there specific places in this particular model car that have been problematic for others? I'd rather not waste my time chasing down the entire vacuum system if there's a common place (or places) that tends to leak....
Thanks -
My question is: are there any areas that I ought to be checking first? Are there specific places in this particular model car that have been problematic for others? I'd rather not waste my time chasing down the entire vacuum system if there's a common place (or places) that tends to leak....
Thanks -
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Joined: Apr 2008
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From: Massachusetts
'02 C320 Wagon
Hmmmm...if you're correct, then that makes this a strange situation. The issue I'm seeing is DEFINITELY related to engine load, and I'm assuming the corresponding vacuum fluctuation. Ideas?
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'17 Jaguar XF
He's correct. In fact the levers that the stepper motors actuate easily break in the early C class. Do you hear any clicking noises coming from behind the dash area when you first start the car?
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From: Massachusetts
'02 C320 Wagon
If the arm is broken, wouldn't that mean that the stepper motor wouldn't be able to change which vents the air came out of? Mine seem to operate fine in that regard - they just don't stay put, at times.
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From: Huntington Beach, Ca.
'17 Jaguar XF
Yes.
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Joined: Apr 2008
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From: Massachusetts
'02 C320 Wagon
Well, no clicking sound. I can hear the diverter flaps moving as I change the dash settings.
But I still get the random change depending on how hard I'm stepping on the gas - what gives??
But I still get the random change depending on how hard I'm stepping on the gas - what gives??
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Thread Starter
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Joined: Apr 2008
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From: Massachusetts
'02 C320 Wagon
The actual dash vents, or the ones I've always called "dash vents" - not the floor vents, not the defrost vents, but the ones that are on the face of the dash. Two in the center, plus two on either side, all controllable with the thumb wheel.
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From: Huntington Beach, Ca.
'17 Jaguar XF
But it works grest when you learn the code.
Last edited by mleskovar; Jun 24, 2008 at 01:11 AM.
Thread Starter
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Joined: Apr 2008
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From: Massachusetts
'02 C320 Wagon
Funny - my brother-in-law drove my car to the store just the other day and when he came back, those were almost his exact words!
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From: Huntington Beach, Ca.
'17 Jaguar XF
[QUOTE=venturaII;2900868]... Can you expand upon what exactly it does in this setting?..QUOTE]
You need to read the owners manual to be totally dumbfounded on all the things the Germans engineered into the car. In recirc it automatically switches to outside air if: after 30 minutes if the outside air is >40F, or after 5 minutes if the outside air is <40F, or after 5 minutes if ec is on.
You need to read the owners manual to be totally dumbfounded on all the things the Germans engineered into the car. In recirc it automatically switches to outside air if: after 30 minutes if the outside air is >40F, or after 5 minutes if the outside air is <40F, or after 5 minutes if ec is on.
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Joined: May 2006
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From: VA
2002 C320
Alright - I'm pretty sure I have a vacuum leak somewhere in my ventilation system. When I'm cruising down the road and have the ventilation set to blow through the dash vents, it takes just a tiny bit of throttle (less manifold vacuum) to make the setting change to the default floor/defrost setting, and it takes a good 30 seconds for vacuum to build back up to the point where the vents correct themselves. From my experience in the past with other vehicles, this is a pretty textbook situation.
My question is: are there any areas that I ought to be checking first? Are there specific places in this particular model car that have been problematic for others? I'd rather not waste my time chasing down the entire vacuum system if there's a common place (or places) that tends to leak....
Thanks -
My question is: are there any areas that I ought to be checking first? Are there specific places in this particular model car that have been problematic for others? I'd rather not waste my time chasing down the entire vacuum system if there's a common place (or places) that tends to leak....
Thanks -
My AC/Heat diverters don't divert. No matter the setting, a little comes out the floor, a little out the dash vents, and a little out the defogger. When I turn on the defogger, more comes out the defogger, but it still comes out the floor and dash a little. Mainly, this is a problem when it is really hot and I want a lot of air to come out of the dash vents, but it won't. The fan runs hard, but nothing comes out (well, a little, but not enough). Any ideas?
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Joined: Apr 2008
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From: Massachusetts
'02 C320 Wagon
I have a quasi-similar issue. Didn't want to get STFF'd by starting a new thread.
My AC/Heat diverters don't divert. No matter the setting, a little comes out the floor, a little out the dash vents, and a little out the defogger. When I turn on the defogger, more comes out the defogger, but it still comes out the floor and dash a little. Mainly, this is a problem when it is really hot and I want a lot of air to come out of the dash vents, but it won't. The fan runs hard, but nothing comes out (well, a little, but not enough). Any ideas?
My AC/Heat diverters don't divert. No matter the setting, a little comes out the floor, a little out the dash vents, and a little out the defogger. When I turn on the defogger, more comes out the defogger, but it still comes out the floor and dash a little. Mainly, this is a problem when it is really hot and I want a lot of air to come out of the dash vents, but it won't. The fan runs hard, but nothing comes out (well, a little, but not enough). Any ideas?
I still have the same problem as before, but I've basically given up on it. The manual does describe some pretty interesting automated climate control behavior, but none of it covers what I've been experiencing.
I checked the stepper motor, and the arm is not broken, and when I manually set the controls, I can hear the diverter flap moving; I just have the issue described by JLD2k3 as well as the semi-random changing of the location of air coming out of the vents. Screwy....
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C230K
Interesting thread. I have a similar problem.
I always keep the dash/front (the ones that blow towards you, not the windshield) vents as the only one that blows. However, if I hit a bump it would switch to blow both front a floor vents and then switch back. It hasn't really bothered me, but if there were a solution, I'd be all ears.
The second part of the problem is that when set on the off position, the ac would turn on then off again. This scared me the first time it happened because I thought the rpm blip that occurs when turning on the ac was an engine problem. Again, this really hasn't bothered me either since I usually keep the ac on all the time.
Anyway, I thought these were characteristic of an electrical problem (ie impossible to fix), but I'll keep an eye on this thread.
I always keep the dash/front (the ones that blow towards you, not the windshield) vents as the only one that blows. However, if I hit a bump it would switch to blow both front a floor vents and then switch back. It hasn't really bothered me, but if there were a solution, I'd be all ears.
The second part of the problem is that when set on the off position, the ac would turn on then off again. This scared me the first time it happened because I thought the rpm blip that occurs when turning on the ac was an engine problem. Again, this really hasn't bothered me either since I usually keep the ac on all the time.
Anyway, I thought these were characteristic of an electrical problem (ie impossible to fix), but I'll keep an eye on this thread.
