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ctrlraven
11-05-2007, 01:13 PM
So since before MVV I believe I have had a vacuum leak and back then it wasn't too bad, low fan speed and cruise throttle position the air would blow out where I wanted it to, if I turned the fan speed up or gave it gas the air would come out the defroster vents (70%) and floor (30%). Well now that is has started to get cold (past month or so) it doesn't matter at what fan speed or throttle position it is always blowing out the defroster vent and very very little comes out the floor. I was talking with a Honda (and general) mechanic next door to my work and he came over and took a quick look to see if he could find the 2-way valve and I think he found it. He said to try replacing it first and see how things are, if it still doesn't fix it then take it to the dealer.

My computer is being dee dee dee and wouldn't let me thicken the line but it's the white piece in the yellow circle. Would this be the 2-way valve and if so is their a part number or any other things I can test or try out? This is located behind the transmission dipstick.
http://i11.photobucket.com/albums/a164/ctrlraven/marauder/DSCF1395Medium.jpg
RF Overlord
11-05-2007, 01:55 PM
My computer is being dee dee deeROFL...I love Carlos Mencia... :D

One way to tell if the check valve in question is bad is to unplug the vacuum reservoir after the car has been sitting for a while. If the check valve were bad, it would let all the vacuum leak out (or more correctly, let air leak IN ;) )

The vacuum reservoir is the flat square-ish thing right on top of the driver's side wheel well. It has a single hose, facing the driver.
fastblackmerc
11-05-2007, 02:10 PM
You can test the valve and the canister with a vacuum pump.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=924 74
ctrlraven
11-05-2007, 02:47 PM
You can test the valve and the canister with a vacuum pump.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=924 74

I love Harborfrieght lol. They always have some weird uncommon tool that I need and always in stock lol. There is one by my old house, I'll have to swing by it and pick that up since my old one-man brake bleeder stopped working.
94_302
11-06-2007, 04:34 AM
Read this thread, I had the same symptoms and it was the o-ring I believe. I did it once and it started back again, however I knew I used an o-ring that was a little loose because I could not find a better fit at the time. 2nd time around I used one with a better fit and it has been working fine *knocks on wood*
ctrlraven
11-06-2007, 10:41 AM
O-ring where is the question?
SID210SA
11-06-2007, 11:13 AM
O-ring inside your head unit....real easy to figure out....once you have it apart you have to pry the metal tabs open and pull out the plungers one by one, BE CAREFUL OF THE SPRING, the one that pulls out the easiest is the one that needs the new o ring....trouble is finding the right size. There is a thread on the subject of fixing this problem.

Mike
JACook
11-07-2007, 02:05 AM
O-ring inside your head unit....real easy to figure out....once you have it apart you have to pry the metal tabs open and pull out the plungers one by one, BE CAREFUL OF THE SPRING, the one that pulls out the easiest is the one that needs the new o ring....trouble is finding the right size. There is a thread on the subject of fixing this problem.

Mike

Yes there is. ;)
http://www.mercurymarauder.net/forums/showthread.php?t=36922

Replace all of them. If you only replace the one that's leaking you'll have another one
leaking not long after...

Also, if you read farther down in the thread, you'll find information on which O-rings
to get, and where to get them...
ctrlraven
11-14-2007, 03:07 PM
Just took my ETAC apart and everything looked fine, all the O-rings were in good shape.

I also found the part for the item in the picture in my original post. It is the A/C check valve, $17-18 from L/M, was worth a try. I'll have to get some new O-rings, replace them and see what happens after that. If it still does it I guess it will be going into the dealer.
ctrlraven
11-14-2007, 07:20 PM
Ok.............


So about 2 hrs ago I was driving home from a service call and turned on my heat of course I just hit any of them since it was going to come out the defroster anyways. I had pressed vent and the next thing I know air was coming out the vent and floor would come out the floor. I played with it on the way back to my shop just to make sure it wasn't a one time fluke and it's working just fine now. All I did was replace the A/C check valve (which I don't think has anything to do with it), un-hooked the vacuum hose to whatever thing on the driver's side fenderwell (heard a lot of air) and pulled the ETAC apart and put it back together.

If it stops working again I'll change the O-rings and if that doesn't work then I'll replace the unit.