Delayed defrost to front blower

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Jul 18, 2018 | 10:50 AM

JaySVX

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From: Eastern PA

Delayed defrost to front blower

I have full auto climate control in my '04. For some reason when I turn on the AC, it always goes to defrost. If I push the front vent button, it'll take 2-3 minutes to switch, if it switches at all. If I press front/floor, it never switches to the floor. Also the blower seems a bit weak. I have no idea how this system works, but I have an 800 mile trip in less than a month, I'd like to get it fixed. Any suggestions?

Jul 18, 2018 | 12:22 PM

projectSHO89

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From: St Louis

Check the vacuum pump for proper operation and that there are no leaks in that system including the remote solenoid assembly. Your symptom is of inadequate vacuum supply when you first start the engine. Might be a leaky reservoir or a lazy pump.

The blower can seem weak for several reasons including having part of the airflow directed to the defroster vents when you're expecting it all to come out of the panel outlets. If ALL airflow volume is diminished regardless of the outlet selected, check cabin air filter (if installed) and check the evaporator core for dirt and debris that might be restricting airflow.

Jul 18, 2018 | 12:29 PM

JaySVX

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From: Eastern PA

Thanks for the info, I am familiar with the auto locking hub causing defrost, wasn't aware that it might be the cause of the whole system.

Any idea where I can find these things? The vacuum pump, cabin air filter, evaporator core? I'm completely willing to throw money at it. I've discovered by the time I'm done dicking around trying to make something work, I've usually spent more than if I just replaced it to begin with.

Jul 18, 2018 | 02:09 PM

projectSHO89

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From: St Louis

Quote:

I'm completely willing to throw money at it.

In that case, take it someone who is familiar with the system and can readily diagnose and repair it without the d*cking around. It will save you a lot of time and aggravation (and maybe money, too since you won't be paying for parts based on guesses).

Jul 18, 2018 | 03:33 PM

JaySVX

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From: Eastern PA

Quote:

Originally Posted by projectSHO89

I prefer to do my own work since i'm able and I don't really trust the area mechanics. I've had more than a few misdiagnosis in past couple years. Like a guy who wanted to replace the cat in my jaguar for $1500 plus labor, when it needed a $13 band clamp. Or another guy that said I needed a $400 reverse lamp. I'm more than willing to do the work, but if the vacuum pump is bad, I'd rather replace it for $50 than try and get it working with shoestring and bubblegum. I could have probably free'd my calipers up and extended their life by a year, but they were only $70 a piece, and I wouldn't have to deal with the headache.

Jul 18, 2018 | 03:45 PM

jwronski

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From: Michigan

I'm no expert on this but I think it is called a PVH solenoid and it is located right behind the battery on the passenger side. I used to have an intermittent problem with the defrost and AC. Then it only worked on defrost all the time. I changed the solenoid and everything is working well now. It was about a $40 part, 10 minute job. Worth a shot!

Last edited by jwronski; Jul 18, 2018 at 03:46 PM. Reason: mistype

Jul 18, 2018 | 04:10 PM

JaySVX

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From: Eastern PA

Is that different from the vacuum pump? I know where you're talking about. Another thing is the ac should feel cooler than it is. Under the hood it's icy, rear air is icy, but dash air seems only mildly cool, or even warm if it's really hot out.