Vacuum pressure dropping on idle

[warren_cox]

Have been noticing in the last couple of weeks that the boost guage has been showing a drop off in the vacuum pressure at idle.

Used to sit at 20VAC quite happily. Its slowly moved from 20 to 19, then to 18, and this morning 17psi VAC.

Between gear changes the gauge flicks back to 21psi VAC.

Any thoughts?

Only mod fitted recently was FMIC, so wondering whether I need to go round and give the jubilee clips a quick tweak now things have settled down. Havent fitted the charge pipe yet, so no doubt when I do there will be more fun and games.

cheers
Warren

 

[Martyn]

It might be a lose pipe or it could possibly be slightly higher due to the increased idle speed on the cold mornings.

 

[surfo]

you have a leak somewere in your gauge line.. look on the conections (T and you gauge)... it happened to me once and the T conector was cracked.

 

[GaryM]

Is it possible to get a brass T piece to replace a plastic one?
Im assuming they are a pretty standard size and all have restrictors on the gauge port?

 

[vern]

Is it possible to get a brass T piece to replace a plastic one?
Im assuming they are a pretty standard size and all have restrictors on the gauge port?

Yeah it is gary, rich had one on his lcr, after plastic o/e one kept cracking dunno where he got it from though, someone on here will know

 

[Pabs]

i find mine differs depending on temp outside. Has been up and down since installing it but always been reading fine

 

[GaryM]

Cheers Vern, been meaning to ask this for a while and have never got round to it.

 

[vern]

Cheers Vern, been meaning to ask this for a while and have never got round to it.

Gary i may be wrong bbut sure he got it from a compressed air suppilers, e.g thorite's off the shelf,he needed it asap anyhow............

 

[surfo]

I could´t find a brass T so I took another plastic one and cover it with black sillicone (the one that is sold on any VW/SEAT/AUDI dealer... and now 1year with out cracking!!!...

greetings.

 

[GaryM]

I could´t find a brass T so I took another plastic one and cover it with black sillicone (the one that is sold on any VW/SEAT/AUDI dealer... and now 1year with out cracking!!!...

greetings.

Any idea of a part number?
Which car has these and what are they used for originally?

 

[Martyn]

If you get desperate, might be worth giving these guys a shout?

http://www.thinkauto.com/

http://www.thinkauto.com/acatalog/Price_List_Hose_joiners_116.html

 

[GaryM]

Cheers Martyn, they look like just the job but the port for the boost gauge needs to be restricted I believe.
The one I received with the boost fitting kit certainly is.

 

[Martyn]

I think the restriction is only to help stop the gauge rattling mate.

 

[surfo]

...

Any idea of a part number?
Which car has these and what are they used for originally?

No, this things doesn´t have part numbers... they are used on some cars for the water of the wippers. is a T conection made of plastic

and yes, the restriction is to avoid rattling...

greetings.

 

[warren_cox]

Wouldn't be surprised. My A pillar Nomad gauge has been on and off more times than a *****s kegs as I have endeavoured to get a decent fit out of it.

Will gave a look at both ends to see whether there is any stress fractures in the pipe.

Car is running too well to have a problem.

Cheers for the advice!

 

[surfo]

cracks on this area doesn´t affect really your car performance...

greetings.

 

[Feel]

just spotted some metal t-Pieces:

http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=MSPORT&pcode=FSEMTP001

 

[GaryM]

I think the restriction is only to help stop the gauge rattling mate.

Rattling? As in noise or needle all over the place?

Would this be a problem if I was to go for a normal T piece like the one Feel posted above?

 

[warren_cox]

Cheers Phil

Got a free 2006 Demon Catalogue in Autosport this month (along with a great sticker book with all the motorpsort events for 2006 for your calendar).

Will get one of these.

 

[surfo]

Rattling? As in noise or needle all over the place?

Would this be a problem if I was to go for a normal T piece like the one Feel posted above?

as in Noise, but it´s rare that this happens, I´m using a normal T and no noise... if you hear any noise you can simply do a reduction on your gauge side by inserting a metalic wire and applying a little heat so the hose reduces a bit.

greetings.