Boost gauge fitment (and holder) help

[Key Walshe]

After a few weeks of issues with my car, it was traced partly to a boost leak on an inlet pipe where it joins the throttle bodies. This was duly replaced (thanks Jas' for the part number!) and that appears to have cured any boost leaks with regards inlet pipes or tubes.

However, the car still isn't boosting fully and figured now is the time to finally fit my boost gauge (Group buy arranged by Si - HPmuirt - over a year ago now!) to see what the car is actually boosting at. The pipes feel quite soft and I imaghine they should be much firmer when at full boost. My next port of call is to get the turbo recon'ed as its never been done and it does blow a little smoke on startup...



That is the style of boost gauge I have so I was wnodering what is the best way to fit this part? I've searched the forum, briefly, and found some of the items I'll need

- several metres of silicone tubing with an internal diameter of around 3mm (roughly how many metres though?)
- plus a 3mm t-piece

Is there anything else I'd need to add to that list? And am I right in thinking that Halfords would have these readily available?

But my main question is, where and how do I fit it? Which pipe does it connect to and how?

Also, the reason the gauge hasn't been fitted is because I never had a holder for it! I've seen the ones on German eBay LIKE THIS which are ally and come with either 'turbo' or the '4 Audi rings'. However, I remember there was a GB on some which had the 'S2 logo' on them -where was these from and does anybody have one they're willing to sell?

Thanks for any help

Kieron.

[Sonic]

I have one of those holders which fits in the middle vent - bear in mind that it does stop you closing the vents though.

From here a section of vacuum hose runs down the air pipe to the passenger footwell, where it joins to a t-piece which also feeds the ECU.

[mcandmar]

I did mine slightly different, there are a few holes before the flap where you can route the vacuum and power lines out, only catch is the vent is permanently shut and cannot be opened because the gauge is in the way. Power feed for illumination was taken off the back of headunit. You need about 1meter of hose to run to the ECU just above the passengers feet, cut the boost line and insert the T-piece.

[Key Walshe]

Cheers for the replies fellas, I'll look at fitting it with the vents open! I usually just have it venting warm air upwards on the window anyways if I do use my heaters, and in warmer weather I'll have it blowing cool air at me so them being open shouldn't be a problem!

Sonic, when you say you 'have one'. Does that mean you have one fitted, or one you're looking to sell? If so, which one is it you have, the S2 logo or 4 rings one? Was fitment easy enough with the gauge?

Also, does anyone maybe have any puics of where the vacuum hose joins under the dash?

[Sonic]

Sonic, when you say you 'have one'. Does that mean you have one fitted, or one you're looking to sell? If so, which one is it you have, the S2 logo or 4 rings one? Was fitment easy enough with the gauge?

Also, does anyone maybe have any puics of where the vacuum hose joins under the dash?

It means i have one fitted

It just clips into place.

The vacuum hose normally just runs directly to the ECU, which is behind the glove box. You need to remove the plastic cover with a 10mm socket and then pull the ECU down. Cut the vacuum hose, add the t-piece and the new hose to the gauge

[nip]

i have a vent boost gauge holder, (cheers jas) , when i fit it i put a rubber seal around tha gauge, so now i can open and close the vent

[adamw]

i made my own gauge holder by useing a spare vent, a piece of 52mm black plastic pipe and some supper glue!
gash it may sound but it has to be the best and most o.e looking vent mount gauge holder ive seen.

ps. i have (nearly) working center vent.

cheers adam

[aRtiS]

I made like this (holder comes from Gerd as well):

[Key Walshe]

Thanks for the pics aRtiS, looks good too - not seen that vent before!

One question for you all, why does it go from the vacuum hose to the ecu? How does it get the boost from there, I'd have thought it would have come from the inlet pipe somewhere after the turbo!

[HPmuirt]

not seen that vent before!

That is the single holder that I was offering as part of the boost gauge GB. I prefer it to the solid ones as the gauge is in the middle and the vent holes match the actual vents nicely...see mine below
Dash merge.jpg

One question for you all, why does it go from the vacuum hose to the ecu? How does it get the boost from there, I'd have thought it would have come from the inlet pipe somewhere after the turbo!

The ECU has to measure the amount of boost in order to control the WGFV. Since this is the only vacuum line this side of the bulkhead, it is the obvious one to tee into.

Cheers n

Si

[adamw]

heres a few pics of my homemade gauge holder.

cheers adam

[Key Walshe]

Ooo I like that Adam! As you said previously, it looks very original - I can only see it on my phone but that looks like it was meant to be there.

How did you do it? Was it a case of cutting a hole in the middle of the vent, slipping the gauge into the space, and glueing it in? Did you fit the gauge into the black plastic 52mm piece as mentioned before and then attach it in? Thanks for the pics, quite inspirational

[adamw]

i got a spare vent just incase i ******ed the good one and set to work.
1. remove the vent and take it to bits so your left with the vertical bars
2. find some black plastic pipe 52mm and mark around the pipe in the middle of the vent and cut out the . i couldn't get a bit of pipe 52mm so i got a 60mm bit cut it to length and choped a section down the middle so when you squeeze it together it has a diameter 52mm. glue and sum jubilee clips or cable ties to hold it together.
3. some careful filing of the bars for a snug fit than glue the pipe in.
4. fitting it back in to the centre vents was more tricky because i used a slightly harder pipe so it wouldn't bend easily. also the depth of the gauge made it fowl against the air flap. i trimed the flap carefuly with a dremel so it just clear the flap(about the size of 2 postage , modified the bulb holder so it didn't stick out as much.
5. wire it up to the glove box light and plumb in the boost pipe under the glove box.

i haven't secured the gauge in with anything because its such a tight fit!

hth
cheers adam