Help with vacuum lines 89 turbo

[CBschnell]

Firstly apologies for so many posts!
There are a few things I'm trying to work out - best described in the images.
The first pic is the vacuum reservoir and the pipe goes through the bulkhead to a Y connector - pic 2. The bottom of Y goes back down to the bulkhead and the vac supply?
[attachment=IMG_5721.JPG] [attachment=IMG_5722.JPG] [attachment=IMG_5727.JPG]
More in next post.

 

[CBschnell]

The other Y connector goes to a pipe with a control valve with broken end...[attachment=IMG_5723.JPG]
Looking at various diagrams it looks like that should go to the brake booster??
I then have the pipe from the wastegate going to this device - presuming it to be some sort of manual boost valve??
A separate question on the wastegate to valve pipe, it had a heat resistant wrapping tied to it - does it need that because it was a bit Heath Robinson??
[attachment=IMG_5728.JPG]
From this valve it goes to the manifold.
[attachment=IMG_5729.JPG]
The second banjo has a Y connector, one of which has nothing attached??
I appreciate any help you can offer. When you have replaced pipes, have you upgraded to silicone and if so, where did you buy - pre-made or buy a length and cut to fit?
TIA
Chris

 

[CBschnell]

I forgot... I also have this pipe - should that be attached to something??? It goes across towards the turbo...

 

[Eldavo]

This should help: https://www.lindseyracing.com/LR/Parts/VACDIA.html

You can use any silicone pipe, worth getting the next size up as well to use over the ends as it shows at the end of the LR page.

Do you have a Dual Port Wastegate? I’d want to follow that pipe back from the suspected MBC to confirm what’s going on. Either way it definitely appears like some stuff isn’t connected up so you will have a vacuum leak.

If you’re redoing all the vacuum lines then its probably worth getting a vacuum manifold similar to this: https://www.ebay.co.uk/itm/133703119792?hash=item1f2153b3b0:g:nTYAAOSw8DVhEkyT&amdata=enc%3AAQAHAAAA4GjKqHWtrl%2BL6gwXVjOdFFMNX02K4WS5udOJYK2%2BCyXBggkySD4zD1uvOyIUrMCvGD%2F5YoYg%2Ba%2Bpzvet6pUhZ5DT1SOhnAxGz3NlUf0fpbKMFU5GiX0imE8kg1fd42AnXLpsrfFmTmRhaxJSmpAHB8BJtH25GfZo6FLu3tHST%2B%2BZe0%2Fy76iTAQxZu9OcYTaugaDFEttUZNPyLT2Y1IUa1xgtNH49Bh9F%2B%2BLKcAl%2BrsWzfxgNkMMgfpDRykHrW6LYm0bZT%2B%2Fo5mrQMC1UjigwGXcDywvpkugMmEXS0zYNqRAg%7Ctkp%3ABFBM1tPhwY1h mounting it on the firewall and running everything on it’s own line with no T or Y joiners.

I use an over braided hose like this: https://www.ebay.co.uk/itm/255027051756?var=554979001060&hash=item3b60cbfcec:g:BeoAAOSwF4hiIOlz&amdata=enc%3AAQAHAAAA4HhYGEe46gqZPLbSTYSGi924rJqTTRHVaDwLe0LvFPbq9xGfHRKtz7dYQZyCBBWte4%2FFipHHb53J3ZdCXJWdzHwEo1v0gAnvpGSquXSMjsRps77IqQtcTE%2FRthmfJexLJsTCbrAEQl02WkzRkH41hyfxqKSF5WsAmL93LDcISFRKtXSIg5DSTsq%2FyWD2AwQFnuW5F6cz0hDvPDI9uDAxgsIS6HwSf%2F2Tf3QkWb%2FUMWvrszaD7u6vTwca0CzIxZD4kzHQ1GsmKtwcREN41wU4Ri5QQf4TPTx%2FuQ%2FRqh2IHDYs%7Ctkp%3ABFBMusDywY1h As it looks a bit more discrete and isn’t as prone to tearing as regular silicone hose.

 

[CBschnell]

Thanks David. I don't have a DPW, just standard unit for now. The vacuum manifold makes sense and is a great price compared to other things I have bought recently! Did you get the 4.5 or 5mm hose? Is there a reference spec for hose diameters you could recommend?

 

[Eldavo]

Manual Boost Controller with a single port wastegate doesn’t make much sense?

No idea what diameter hose I used - sorry.

 

[CBschnell]

Thanks again David. I’m a novice with some of this stuff so learning a lot in a short period. I wondered what the red valve was and I assumed it is a MBC as it’s in-line with wastegate hose. Perhaps they removed an aftermarket WG and left the MBC - nothing in the records.


I should have checked spec of the vacuum manifold before asking hose size, it’s a 5mm connection.
cheers
chris

 

[Eldavo]

If you’re running standard chips, fuel pressure regulator and wastegate then I’d be inclined to remove the manual boost controller and plumb the cycling valve back in.

Essentially you would be doing step 6 here: https://www.lindseyracing.com/LR/Parts/WASTEGATE.html But in reverse!

 

[scam75]

Could be a bleed valve of some description to allow for higher boost whilst still using the single port wastegate.

When I got my car it had a bleed valve, and the standard single port wastegate, and a Superchips ECU chip was installed. It made about 280bhp like that, can't remember the boost level and it was pre-AFR gauge so no idea how the fuelling was, but it seemingly had ran for many years like that without issue. I think the cycling valve was all still connected. Removed all that stuff when I got the dual port wastegate, Promax chips, 3 bar FPR and proper manual boost controller. I think I may still have the chip somewhere.

And while I'm at it, that broken blue/black valve is a one way valve and can be replaced with this:

https://www.ebay.co.uk/itm/183606727909?var=692875128647

This replaces the blue/black non-return vacuum valve on the turbo at a fraction of the price, near the bulkhead.

Stuart

 

[CBschnell]

Thanks Stuart. I do trawl the web for answers and solutions before putting stuff on here - honest guv! However it's not always easy to find with the different year models and lack of pictures. Per your suggestion with the check valve, where does it connect to? All the diagrams I have looked at points it to the brake servo, but I can't see anything there. Interestingly under the brake reservoir there are two pipe connections, and in pictures I see brake lines coming off both those but on mine, one nearest to the firewall is just closed off. I'm just using these as examples of trying to find the right information, and whether my car is standard or modified, and if modified, to what and for what reason. I have been going to Clark's Garage and Pelican for info as well as forum searches, but if there are better resources, please recommend them to me. Anyhow I do appreciate the wealth of knowledge on here and people sharing it.

Back to the matter at hand, although I have thick binder of receipts, there doesn't appear to be anything regarding mods. FYI the cycling valve is there. The DME was hidden in there behind a couple of black boxes - going to take that out and inspect.

Thanks in advance,
Chris

 

[scam75]

Thanks Stuart. I do trawl the web for answers and solutions before putting stuff on here - honest guv! However it's not always easy to find with the different year models and lack of pictures. Per your suggestion with the check valve, where does it connect to? All the diagrams I have looked at points it to the brake servo, but I can't see anything there. Interestingly under the brake reservoir there are two pipe connections, and in pictures I see brake lines coming off both those but on mine, one nearest to the firewall is just closed off. I'm just using these as examples of trying to find the right information, and whether my car is standard or modified, and if modified, to what and for what reason. I have been going to Clark's Garage and Pelican for info as well as forum searches, but if there are better resources, please recommend them to me. Anyhow I do appreciate the wealth of knowledge on here and people sharing it.

Back to the matter at hand, although I have thick binder of receipts, there doesn't appear to be anything regarding mods. FYI the cycling valve is there. Your and David's comments got me thinking, so I explored the DME... Well it doesn't have the metal bracket behind the wooden floor piece, and it is definitely not a Bosch unit! The black box is nondescript with a couple of numbers but no manufacturer's name. Of even more concern, the unit is hardwired! Do any of your recognise the type of unit?
[attachImg]https://www.porscheclubgb.com/forum/download.axd?file=0;1130407&where=message&f=IMG_5742.JPG[/attachImg]
Thanks in advance,
Chris

OMG, that is a can of worms for you to unravel! I have never saw that before. It would suggest modifications of some (dramatic!) sort have taken place. Going back to the bleed valve to start, it will simply bleed air off on route to the waste gate, meaning higher manifold pressure needed to open the gate, meaning higher boost pressure than the ECU sees. Dangerous if not catered for by the mapping. I would suggest if nothing has melted up to this point, the mapping is catering for higher boost. Be interested in the AFR's though. It looks to be situated correctly for this and fits with my idea. You need that black box explored asap!

For the blue/black valve, it connects under the manifold near a y piece, I think. I'm collecting my car later today from the paint shop. I will properly check then for you.

Stuart

 

[944Turbo]

I think that black box is part of the immoboliser / alarm system I am pretty sure my coupe has something very similar and is still fitted with the 'original' dealer fit immoboliser (that needs the electronic 'key' (dongle) inserting prior to start).
The red thingy looks simialr to a boost enhancer (ball on a spring to delay wastegate opening flow - it has to 'lift the ball first against the spring pressure) or a bleed valve and it may mean the cycling valve was bypassed if they wanted to run a bit more boost or avoid leaks. Or it might just be a bleed valve to leak some of the 'wastegate open' signal - again to delay wastegate opening and maybe run a little more boost.
Tony

 

[944Turbo]

Pretty sure the blue/black valve should connect to the vacuum reservoir in the scuttle area from memory or maybe through to the heater controls inside the car
The black elbow may connect to the pipe that goes to the nipple under the throttle body, not easy to spot but a commonm one to fall off - could have come off and the pipe was removed?
Tony

 

[944Turbo]

Actually looks like the blue black valve goes to the brake booster in the 2nd drawing in this thread (but close to vac reservoir )
https://rennlist.com/forums/944-turbo-and-turbo-s-forum/404653-vacuum-line-diagram.html

 

[944Turbo]

Had a quick look at the cab, the blue black does go to the vac reservoir but there is a 'T' first - I think the other branch goes to the valve that is to do with the emmissions carbon canister (by the brake servo) the only pipe I could see on the brake servo was larger diameter. Then I had to come back inside on a work call will check later if I get a chance - also disocovered I need new bonnet struts (now its cooler) so need to sort a prop to get a good look!
Tony

 

[CBschnell]

Thanks for replies. i must have been deliriously hungry as I looked for EMC at lunchtime - came back after lunch and past the black boxes and cables there was the EMC - whew, sorry for confusion. I took it out and opened it - didn’t look like it had been opened before and I’m presuming that is standard chipset.

 

[Eldavo]

EMC are in Birmingham

That looks like a standard chipset in the ECU.

In post 4 I put a link to all the different Vac diagrams on the Lindsey Racing website.

Having looked at my car tonight I can confirm that the pipe goes from the vac canister to a T - one end goes to the connection in the bulkhead and the other end goes via the blue/black valve to the manifold. I don‘t have the charcoal canister and emissions gubbins in my car.

 

[944Turbo]

I forgot... I also have this pipe - should that be attached to something??? It goes across towards the turbo...
[attachImg]https://www.porscheclubgb.com/forum/download.axd?file=0;1130291&where=message&f=IMG_5730.JPG[/attachImg]

looked again at the images that is the back of the head isnt it - the line to the throttle body would normally T from the front of the head by the fuel rail damper at the front of the head - I think the open T usually takes a signal forward - maybe to the dampener? where there is another T
Tony

 

[CBschnell]

Thanks everyone - great input. I will follow up on my progress. I have received back some of my suspension parts, so back to that for the moment.