guards red

Hi,

Sorry for the delay, working!

1/ that's exactly what I mean. The manifold is upstream and generating the vacuum via the engine (as I am sure you know). Disconnect everything from the check valve and connect the gauge to that and test. The check valve is all that is between the engine and the gauge so any leak here will be the valve assuming the pipes and the venturi tubes are not damaged.

2/ If you then connect each pipe in turn back onto the valve multi tube take off (the pipe that collapses!) and carry out the leak test. Each should hold vacuum. The one that doesn't is the issue. From memory the pipe has take offs for the tank (the main thick one), one for the AC (HVAC) system, the resonance flap/ varioram solenoids and one for the reversing valve solenoid. This latter part is right at the front of the engine on top of the pipework for the electric fan. It engages when you select reverse to prevent exhaust gases entering the cabin when you're going backwards. It operates a flap in the pipework and draws air in from the snorkel under the engine lid.

Part number for the valve is: 930 110 667 01. Note they've had quality control issues, my replacement failed within months and a further new one was dead out of the box!

Hope this helps
GR

skl2

Awesome...I think I finally understand the process for correctly checking, and accurately diagnosing where my issue is!! Thank you!! I will check back in this weekend with my findings.

skl2

Update: I took apart the fender liner and accessed the reservoir tonight. It is fine and did not have any leaks. I pulled the hose that goes into the reservoir and hooked up the mityvac and added vacuum....it slowly faded signaling a leak somewhere. Obviously it could be from any number or places given I did it down stream of the TT hose but I am willing to bet its the check valve now. I have one on the way and will check all of the hoses I can reach at the same time I replace the valve. How hard is it to remove he VRAM with the engine in the car?

guards red

Hi,

The varioram manifold can be removed with the engine in the car. It doesn't even need to be lowered. It's just a matter of removal of parts to get at it, mostly the heater blower fan, the A/C compressor, the airbox and MAF.

The hardest part is the accelerator cable. The trick here is to disconnect it at the pedal end and pull the cable out from the outer sleeve as the manifold come out.

Check the rubber unions between the intake runner legs and the cylinder head unions as these perish and crack. Lube them to ease the legs back in when reinstalling.

The valve has crush type, one time use clips for the connecting pipe work. These can be a pain to resinstall but other than that I would consider just doing the replacement in situ. You can use jubilee slips if you're not a stickler for authenticity.

Regards
GR

bobt993

As GR mentions the throttle cable is a PITA to get back in, but not too bad removing. You also have the cruise control that clips in to throttle lever. I would suggest lowering the motor about an inch to get the vram out. You likely still have the sound mat in place and it will rub against it pretty hard. Also remove the top of the fan shroud or it will get damaged (tear in the rubber). Replace both check valves while you are in there since the brake booster uses the same arrangement and you don't want that one going bad. ( I have had this happen on a race car). You can install a hose clamp after removing the one shot clips, but do not overtighten or you will crack the check valve housing. While the vram is out inspect and likely replace the smaller tree that connects to the slide valves to the actuator. Check that the resonance flap is not leaking ( it likely is). Clean it and reseal it . These are pretty easy and straight forward jobs. Also cover up your intakes and inspect all 6 cylinders for debris falling in before reinstalling. I would also clean the fuel injectors and intake runners while the vram is off. Very easy and you are already there. Be careful while removing the 3 allen heads that hold down the intake runners as they can snap off.

k722070

if you are not psyched about removing the varioram intake,
maybe another strategy would be removing the tree(2 allen bolts) and then reaching around to the throttle body area and disconnecting the 2 hoses that run from the tree. one connects to the varioram the other to the rubber section between the throttle body and air box.
in this case you are still dealing with the throttle cable area hassle, but only loosening 2 hose clamps.
probably still have to lower the engine, but at that point you could remove the tree and then reach around for those hose clamps. at that point you could decide which is the bigger pain, dealing with blind hose clamps or removing the entire intake.
just a thought.

skl2

Thanks guys....At this point I might just see if I can change the check valve in situ. If that doesn't cure the problem, I might just look at dropping the engine this winter and doing a major maintenance/refresh. At 15 years old, all of those hoses and seals are probably due to be changed anyway!

ToreB

skl2, dId you check the vacuum line to the resirc flap and according electric valve in the trunk? I would do this before even thinking of dropping the engine. The check is done in minutes. My HVAC details web page have the details where to look.
Cheers,
Tore

skl2

Tore, your website, explanation and pics are awesome. I will check that hose in the trunk tonight! I have had my CCU out 3 times in the last week, so I will also check behind it to make sure I didnt dislodge anything. Thanks.

skl2

Update - I have varioram! I took Tore's advice and checked the vacuum line in the front trunk and behind the dash. As soon as I looked up under the dash, I could see the hose just hanging there. Reached up, stuck it on the recirc flap and took it for a ride. Vram kicked in as it should!

That all being said, Im going to go thru my vacuum system in detail this weekend and still change the check valve....I figure it can't hurt given its age! Thanks everyone for all of your help and explanations!

ToreB

Good news, congrats on your findings skl2!
Testing most HVAC components can be done in minutes, see my quick guide on my HVAC page.
Cheers,
Tore

MarkD

fantastic!

Good one Tore

skl2

Thanks for your quick replies to my email, Mark. I wish your shop was in my backyard....I would be there all the time Will be in touch when I am ready for Stage II's!