Well, warm weather is approaching in NC. The car is covered in yellow pollen so I don't want to ride with my windows down.

When I run the AC - I hear the climate control relay click and then the center vents quit blowing AC and it starts blowing for 20 seconds out of the defrost vents. Then it switches back. This goes on continually.

I think I posted this before, but cannot find the post. I have searched for all my posts and cannot find it.

I replaced the climate control unit last year. I think it is under warranty. My parts guy says it isn't the unit. He says it is a vacuum leak. But if so, why would the relay clicking right before it changes? I would think if a vacuum acctuator or one of the things on that crossover block had gone bad that it would either stay open or shut.

My question - could it be the temperature sensor over the rear view mirror? It switches between vents even if I have the temp wheel all the way to bypass the automatic feature.

I need to know where to start with this. The dealer wanted $200 just to diagnose it. That is rediculous!

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1982 300SD Light Blue
2002 Honda Accord SE
1974 Toro Wheel Horse Tractor
2000 Toyota Tundra Pickup

You have quite the problem there Will.

I don't believe that the temperature sensor can be the issue if you have eliminated it by turning the temperature wheel all the way to full cold to bypass the automatic control.

But, I remain perplexed as to what could cause this. I certainly don't see a vacuum leak being the problem.

I think the dealer charges that $200 when they see us in our old cars. They figure that when the price of the repair $1,000+ is spoken we run. The dealer has far to many ignorant yuppies that never pop a hood to charge the crap out of em. Why should they bother with us? The customers they like have no knowledge & credit cards.

I dont agree with the way they operate but thats how it is.

Well Kirby,
My mechanic I use on occasion at the dealer is excellent. He has been there 30 years and has quite a following. He only works on the older models in the triangle area of NC. But he does not set the labor rates.

My dealer's labor is about $85 per hour. Less than the Chevrolet dealer down the street by $5 per hour.

I need some help with diagnosis. If someone will tell me what to test, I will go buy a Mityvac and do it. I just need some help with where to start.

I think it is a defective climate control, but that is just me.

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1982 300SD Light Blue
2002 Honda Accord SE
1974 Toro Wheel Horse Tractor
2000 Toyota Tundra Pickup

I have a spare unit that I purchased from another forum member if you want to borrow it for testing..............

W124 climate control vacuum pod replacement

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I don't really think you have a vacuum issue, as your relay clicking seems to rule that out. It sounds as if your CCU is weirding out. (very technical terminology)
That is an awful nice offer from Brian, and a nice way to rule it out.
I'm still reeling in shock that you don't have a Mityvac yet.......

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Jimmy L.
'05 Acura TL 6MT
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Gone:
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