Does your climate control only blow out of defrost??? - PeachParts Mercedes-Benz Forum

brandlj · #1 04-22-2011, 12:43 PM

Handy Hint!!

I just changed glow plugs on my 86 300sdl, and cleaned my intake manifold and replaced my intake gasket. I also just received my speedometer back from Overseas Speedometer in Austin Tx to fix my gears. I put everything back together. All went well, all looked good and then the test drive.....
My air was only blowing out the defrost vents. OH NO!!!! What did I do? Has my CCU gone belly up???? NO. I accidentally detached the vacuum line at the vacuum pump that goes to the interior CCU vacuum tree. No vacuum.... the system reverts to default which is defrost only.

5 minute fix and all is well. My hint to this problem, transmission shifted perfectly, the car shut off perfectly, but I wasn't hearing my main air flap making noise when I started the car.

It came disconnected at the 4 way rubber connector just above the vacuum pump!

WHEW!!!! What a relief!

tangofox007 · #2 04-22-2011, 01:31 PM

Quote:

Originally Posted by brandlj

...the system reverts to default which is defrost only.

Same thing happened to one of my tires after I ran over a nail. It reverted to its default condition: flat!!!

And my fuel tank is approaching its default condition right now.

brandlj · #3 04-22-2011, 04:04 PM

Hopefully your bank account won't revert to the default situation when you have to go fill up with diesel!! $3.99 a gallon here. OUCH!

dieseldiehard · #4 04-23-2011, 01:49 PM

$4.59 for diesel here

The real funds drainer on that car will be a cracked head
I just went thru that, living in denial that it would happen with one of my two '87 300Ds and finally it happened. Still its worth the risk, just love the '87's!
DDH

brandlj · #5 04-23-2011, 02:36 PM

Quote:

Originally Posted by dieseldiehard

$4.59 for diesel here

The real funds drainer on that car will be a cracked head
I just went thru that, living in denial that it would happen with one of my two '87 300Ds and finally it happened. Still its worth the risk, just love the '87's!
DDH

Yup, 122,800 miles on a 14 head. You never know if and when it will happen.

JPUTT · #6 04-23-2011, 11:00 PM

Have a 87 300SDL that had a 14 head replaced at 190k with a 16 head. At 280k I had to replace the 16 head with a 22 . At 305k+ doing good.

I had a bad EGR valve that was robbing all my vac and causing the HVAC to defrost only and shift terribly. Bypassed the EGR and everything fixed itself.

brandlj · #7 04-24-2011, 06:45 PM

My EGR is bypassed also with a golf tee in the line. Looks goofy, but works just fine. I have had the EGR blocked for about 3 years now and the inside of the intake manifold and crossover pipe were not too bad at all.It did not take much to clean them up. When I had the intake manifold off I was pleasantly surprised how clean the intake valves looked also.