Air recirculate not working. 2-minute DIY?

Bukowski · 06:45 PM

Late MY:

Air recirculate button has light, makes a click sound. That's about it. Smelly air still gets in. Read real quick about the solenoid, some lines - can someone give a 20 words or less DIY instructions to get the recirculate working again?

Note - edited

Dmitry at Pelican Parts · 10-13-2016, 01:23 PM

What year/model is this issue affecting?

Bukowski · 10-13-2016, 01:42 PM

Hi Dmitry at Pelican Parts - '87 944 NA.

djnolan · djnolan's Garage

Hello Friend,

Make sure the one-way vacuum valve is installed in the correct direction. It is on the line coming off the brake booster.

Tom944 · Tom944's Garage

My solenoid valve kept clicking when the ac was on. Also, it did not click when I pressed the recirculate button. I replaced the solenoid to fix it.

I recommend that you remove the glove box and look at the solenoid to see if the vacuum lines are connected. It is the Lowe left solenoid on the side of the air conditioning/heating box. Also, look at the two vacuum valves under the plastic cowl below the wipers. You can see one on each side of the fan box. The solenoid opens the vacuum line to these and they move the flaps to recirculate. Char know all the lines between them.

Bukowski · 10-15-2016, 03:52 AM

I'll take a look!

Bukowski · 08:56 AM

I see two solenoid-looking things ; the top one clicks. Looking for other things now. I'll get a pic sometime.

BTW - is the tube supposed to connect to the glove box on that funny plastic 90-degree fitting? ANSWER: YES! why the H is the vent through the glove box?! anyways... is it possible to clean out these air ducts? I can see the rectangular one....

Bukowski · 10-15-2016, 08:19 AM

Ah ha! That's what those vacuum things do!

Ok so if there's no vacuum suction by touching my finger, and the recirculate solenoid clicks, ....? I'll check the brake booster later on...

Also I think I have the diagrams understood now - 813-25 and 813-05.

Is the solenoid for '87 944-659-215-__ 01 or 02? The PET has both, don't understand.

Bukowski · 10-15-2016, 08:22 AM

Also what's that sensor there for?

Tom944 · Tom944's Garage

Only the -O2 solenoid is available. When I replaced mine I cut and soldered the wires, which was a pain. I could not pull the pins out of the connector. Both solenoids connect to one connector. When you disconnect the lower vacuum line to the solenoid you should hear it hiss as the vacuum is released, even with the car not running.

Bukowski · 10-15-2016, 09:02 AM

Quote:

Originally Posted by Tom944

...When you disconnect the lower vacuum line to the solenoid you should hear it hiss as the vacuum is released, even with the car not running.

well, its tight in there. thinking about how to remove 944 572 416 00 to get some room... but I removed the hoses from the vacuum actuators, no sounds.... I see there's a connector that ought to be up on the blower motor....

... about that one-way valve - seems the correct orientation, smaller part away from booster - judging from the PET illustration.

Bukowski · 10-15-2016, 11:35 AM

time for piccies! maybe upside down! oh well!

side of heater core showing solenoids:

you know this spot? both sides? well, there's a flap in there (this is news to me and I've had the car a while now)!

... btw the sensor is in that pic too.

oh look, there's some badly rusted levers here - I wonder if...(sprays WD-40, works levers by hand)... yes!

(I really like that pic for some reason - kind of Ridley Scott "Alien" style maybe?)... and yep, a rusty rod is going into the vacuum actuator - yeah, THAT thing! never knew what it did!

here's a close up. look for BROWN!

so far, so good. hoping this'll shape up into another easy peasy DIY.

Tom944 · Tom944's Garage

The solenoids look to be connected correctly. Mine is an '87 that's why there are two actuators by the fan motor. The second solenoid is for the heater flap(I think). Does your heating turn on and off ok? It uses the same vacuum source.

Bukowski · 10-15-2016, 03:17 PM

Heat is ok.

I'm thinking to try the vacuum actuator first.

Bukowski · 10-21-2016, 11:47 AM

Heat works.

If there's no hiss after disconnecting the solenoid, what is the next thing to check?

I'm solving this entirely not in order.

Tom944 · Tom944's Garage

Next I would pull the vacuum hose off of the actuator at the fan and see if there is a vacuum there when you press and release the switch (and hear the click). You will need to have the engine running. You probably did not get the hiss when you disconnected the line before because you have a slight vacuum leak somewhere else and the reservoir was empty.

Bukowski · 10-22-2016, 09:23 AM

Thought I tried that... I'll try again.

What's the next further thing in the vac system?

I noticed there's no Clark's section on vacuum. Saw 777's vacuum leak post on That Other Porsche Forum....

Bukowski · 01-05-2017, 10:48 AM

anyone have a link to the silicone tubing at Pelican that I need to replace this?

djnolan · djnolan's Garage

The vacuum supply for the recirc vent comes from the brake booster and there is a plastic one-way check valve there to insure there is no back pressure when braking. if the valve is clogged or installed in the wrong direction then...

Bukowski · 06-23-2019, 08:18 AM

I've recently discovered a vacuum port has been disconnected from the vacuum line since I bought the car. The port is behind the engine, passenger side. I am hoping to get this fixed one day. I have no idea why it would have been disconnected - or perhaps it was too much fuss to put the vacuum line in.