Vacuum system advice needed, and one transmission question too...

[Spaceboy3000]

Hey Everybody,

First off, thanks for all the help this board has already provided! (A/C problems in Georgia in mid-summer!!) Now I'm tackling a few other things and have a few more questions:

Here's what I am working on: a 2003 A4 B6 (AMB motor) manual trans, FWD

Coolant has been leaking from back by the flange, so you know what that means...! I changed the flange and also the hose coming off the bottom of the flange with the plastic “click” connector. I'm glad I ordered that hose too, because the PLASTIC FITTING was the only thing leaking. I found that the flange that I had put in, about 3 years and 40,000 miles ago was actually doing just fine.

**** ALSO, though, I had noticed that the valve cover gasket had started leaking quite a bit, seemingly from more than one place. I've heard that a common cause is that the block breather system is messed up, leading to pressurization of the case, and thus oil leaks.

So before I did the flange, I started by changing the valve cover gasket. I wasn't able to get under the cam chain tensioner to change that small seal there, but it doesn't appear to be leaking from there anyway, so I left that part alone. That seemed to go fine, AFAIK.

I also ordered a few new parts, in hopes that I might avoid any more possible crankcase back pressure (and then oil leak) problems. I'm replacing the breather valve, the suction jet pump and the pressure relief valve (black "pancake" valve?). So if I make sure that those parts are all working and hooked back up correctly, I SHOULDN'T have any more breather problems out of the motor, right??? ( I might also order a bunch more viton check valves and replace all of those too...) Does this sound about right? I read about deleting some stuff out of the system, but at this point, it seems probably simpler to keep it stock.

TWO MORE QUESTIONS:

1) When putting everything back together, I found a loose hose end. It is a pretty thin vacuum line that I think is attached down by the right motor mount, maybe to one of the intercooler duct tubes(?) I think that it was routed up and around the front of the motor. The upper timing belt cover has clips for two hoses – one fat and one skinny, and I think this was the skinny one. Where should the other end of that hose go? I've been digging through diagrams and haven't figured this one out yet.

2) In the past 6 months or so, I have found that the car is hard to shift into a gear (first or reverse) when the motor is cold. It gets easier as I start driving. I checked the hydraulic fluid, and bled the clutch slave cylinder, but that didn't change anything. I'm positive that the transmission could use new fluid, and have been reading posts about the types, etc. I'm leaning towards the Redline MT-85 (75W85 GL4). It seems reasonably priced, too. When I drain the old stuff, I am going to see how it looks, and measure the quantity too. Hopefully some new trans oil will help with this. Any suggestions on that? Also, a transmission that is just hard to put into gear when the motor is cold is probably NOT an indication of a clutch problem, is it? Everything else seems fine with the gearbox from what I can tell.

I'm all ears, guys. What can you tell me?

Thanks!!

[jacobsen]

Hey Everybody,

First off, thanks for all the help this board has already provided! (A/C problems in Georgia in mid-summer!!) Now I'm tackling a few other things and have a few more questions:

Here's what I am working on: a 2003 A4 B6 (AMB motor) manual trans, FWD

Coolant has been leaking from back by the flange, so you know what that means...! I changed the flange and also the hose coming off the bottom of the flange with the plastic “click” connector. I'm glad I ordered that hose too, because the PLASTIC FITTING was the only thing leaking. I found that the flange that I had put in, about 3 years and 40,000 miles ago was actually doing just fine.

**** ALSO, though, I had noticed that the valve cover gasket had started leaking quite a bit, seemingly from more than one place. I've heard that a common cause is that the block breather system is messed up, leading to pressurization of the case, and thus oil leaks.

So before I did the flange, I started by changing the valve cover gasket. I wasn't able to get under the cam chain tensioner to change that small seal there, but it doesn't appear to be leaking from there anyway, so I left that part alone. That seemed to go fine, AFAIK.

I also ordered a few new parts, in hopes that I might avoid any more possible crankcase back pressure (and then oil leak) problems. I'm replacing the breather valve, the suction jet pump and the pressure relief valve (black "pancake" valve?). So if I make sure that those parts are all working and hooked back up correctly, I SHOULDN'T have any more breather problems out of the motor, right??? ( I might also order a bunch more viton check valves and replace all of those too...) Does this sound about right? I read about deleting some stuff out of the system, but at this point, it seems probably simpler to keep it stock.

TWO MORE QUESTIONS:

1) When putting everything back together, I found a loose hose end. It is a pretty thin vacuum line that I think is attached down by the right motor mount, maybe to one of the intercooler duct tubes(?) I think that it was routed up and around the front of the motor. The upper timing belt cover has clips for two hoses – one fat and one skinny, and I think this was the skinny one. Where should the other end of that hose go? I've been digging through diagrams and haven't figured this one out yet.

2) In the past 6 months or so, I have found that the car is hard to shift into a gear (first or reverse) when the motor is cold. It gets easier as I start driving. I checked the hydraulic fluid, and bled the clutch slave cylinder, but that didn't change anything. I'm positive that the transmission could use new fluid, and have been reading posts about the types, etc. I'm leaning towards the Redline MT-85 (75W85 GL4). It seems reasonably priced, too. When I drain the old stuff, I am going to see how it looks, and measure the quantity too. Hopefully some new trans oil will help with this. Any suggestions on that? Also, a transmission that is just hard to put into gear when the motor is cold is probably NOT an indication of a clutch problem, is it? Everything else seems fine with the gearbox from what I can tell.

I'm all ears, guys. What can you tell me?

Thanks!!

The Long Haul as you described sounds like it may be going to the diverter valve.

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[Spaceboy3000]

Yes, looking at photos of the diverter valve, I am pretty sure that is where that vacuum line is coming from - the diverter valve. It looks like that vacuum line comes around the front of the motor and goes somewhere on the intake manifold, right? Any guesses where on that manifold it would attach to?

********** Sorry, I was wrong about it being the DV. See my post below...**************

[jacobsen]

Yes, looking at photos of the diverter valve, I am pretty sure that is where that vacuum line is coming from - the diverter valve. It looks like that vacuum line comes around the front of the motor and goes somewhere on the intake manifold, right? Any guesses where on that manifold it would attach to?

You should see a nipple on the intake manifold on the very front of it directly above the alternator.

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[5ktq]

Diverter valve hose goes to the N249 solenoid, under the intake manifold, towards the firewall from the throttle body. There's two identical solenoids under there, it goes to the one nearer the front of the car.

I just replaced all my breather stuff that was sludged. replace everything in this pic, (except the metal pipe, I cleaned that). Clean the other metal pipe, and I also replaced the PRV and SJP. everything was filthy. Metal pipes sludged to 1/2 volume. grooooss.



That nylon 'L' is usually cracked in 5 pieces. That pic is for early cars like mine, later are somewhat different

[Spaceboy3000]

Hi Again,

Well, I was confused as usual. The DV, or combi valve is the silver metal canister behind the block, and there IS a skinny vacuum tube attached to that.

For my situation, the part in question (from looking at a lot more pix) is in fact the "mechanical recirculation valve", and the vacuum line snaking up off of it. See my stolen/borrowed photo from somebody else's post. I'm needing to find where the OTHER end of that vacuum line ends up, and I am thinking that it should go around the front of the motor to one of the solenoids under the manifold.

http://i1382.photobucket.com/albums/...pspnmfl6vb.jpg

Hopefully that photo posted from photobucket....!

[Spaceboy3000]

Sorry Guys,

I had the wrong part there. Its not my diverter valve thats lost its vacuum tube. (I posted more on that issue above).

HOWEVER, I do have all of the parts in your picture removed right now. (And OF COURSE that plastic "L" is busted, and a replacement is on its way.....)

I am replacing the breather valve (pretty similar to the pictured green one, although mine is like a "tee" since my version has one more line coming off of it.

While we are on the subject, thought, I DID take off my diverter valve to check it out while I was in there. I can't tell if it is operational (although I'm not getting any CELs) but I hear that it really isn't that important except for starting in cold weather (NOT a concern for me). New ones aren't cheap (!) so I figure I'm just going to put it back as is.

On the good side, all of the tubes pictured above only had a LITTLE bit of residue in them, but no "sludge" at all, so the plan for now is to just clean them up, and reinstall them (with the new breather). My main concern is making sure that the block breather setup doesn't quit working (again?) and lead to that new valve cover gasket leaking, etc, etc.

[diagnosticator]

Yes, looking at photos of the diverter valve, I am pretty sure that is where that vacuum line is coming from - the diverter valve. It looks like that vacuum line comes around the front of the motor and goes somewhere on the intake manifold, right? Any guesses where on that manifold it would attach to?

********** Sorry, I was wrong about it being the DV. See my post below...**************

That hose connects the DV to the N249 solenoid valve under the manifold. From there, it is attached to a nipple on the front of he intake manifold beside #1 intake port runner.

[Spaceboy3000]

OK, Now I realized that I was even confused about my own confusion !!!!!

So to make sure that I FINALLY have this straight, the DV, or diverter valve, is the same thing as the ""mechanical recirculation valve"" according to Bentley, which is down below the turbo. Right?

And the silver canister BEHIND the block is the combination or "combi" valve for secondary air injection..... Right? Right.

THANK YOU!!! for clearing up (hopefully) my confusion regarding some of these maddening vacuum systems!



Any thoughts on my transmission question in my original post? (Its at the end of the original post)

[5ktq]

Yep. DV / recirc connects to the front solenoid, kombi / sai connects to the rear solenoid. They're right next to each other, under the intake manifold. (the electric things that grind up your hands when removing that 'L' breather tube).

For the trans question.. I don't know what the problem is, but it isn't the clutch.