RDB

Would Appreciate some advice please,Just had Boost Gauge fitted to My00 Scooby,by my local scooby dealer,its standard apart from K&n Filter,Ninja Backbox,And Baily Dump valve,..
The Mechanic who installed the Gauge told me,that i should not expect boost of 1 bar,because i have dump valve fitted,i have just taken it for a spin.maximum revs reached where 4.5k boost gauge indicated 0.5 wich i think equates to 7psi.
now im wondering if the mechanic was correct about the dump valve,or there is something wrong with my turbo?if anyone as any ideas.please let me know,im not very mechanicaly minded,but i would appreciate any ideas.
thanks RDB

grahamfrary

Should give about 1 bar from around 3000rpm pulling hard in fifth. Don't see why the dump valve would make any difference on boost.

vulnax999

iTrader: (7)

If you only see 7 psi / 0.5 bar then you are on limp home mode boost, or else the garage left a hose off the installation so wastegate seems boost too early ( boost control solenoid not in the circuit to give you proper boost! ) and so waste gate opens on its mechanically set boost, not what the ECU / boost control solenoid should control.

Also you say max revs you reached were 4500 rpm .. then definitely limp home mode .. some thing is wrong. TAKE IT BACK PRONTO! and get them to fix it, and any other damage caused by their errors.


You should get around 13 - 14 psi / 0.9 - 1.0 bar boost by 4000 rpm IIRC normally. And 7000 / 8000 rom rev limit depending if WRX/UK car or an STi respectively.


PS - vent to atmosphere dump valves do upset the ECU as it ( the VTA ) dumps measured air to waste, so the ECU puts in too much fuel and so car runs rich. That could cause higher fuel consumption, bore wash/more wear, pops and bangs from exhaust, catalyst damage etc. but not low boost or low rev limit.

Fuzz

shakes head at advise from so called "mechanics"
You should make around 1 bar boost.

Alternatively..

You could be in limp home mode where the ECU holds back on boost pressure because of a problem.

Your Dump valve could be leaking like a sieve.

Your numpty mechanic installed the gauge incorrectly.


Andy

vulnax999

iTrader: (7)

nod agree with Andy! Hi matey!

Fuzz

evnin

RDB

Thanks Guys for your Advice,I shall Put My Standard Dump valve back on,See what happens then?.i shall also check all hoses,etc,i dont realy know wich hoses are wich,?but i will check every one!.
if then problem still persists i shall return to my dealer which fitted the vta valve..and once again thanks For your help in the matter...

RDB..

vulnax999

iTrader: (7)

Sounds a good idea, try what you can and see. Failing that, go back to the dealer / installer for advice / a fix.

Just make sure all hoses to and from turbo and boost solenoid ( it's on the driver side wing in front of the suspension mounting, a goldy cylinder ) are all attached OK and the one to the air inlet ( the black box called the resonator ) is still attached.

And look at hoses into and out of turbo to make sure the big hoses are securely attached, and also they haven't cracked or split - My bendy flexy one into turbo cracked badly where the jubilee clip secured it and leaked like a good 'un!

RDB

Thanks Vulnax Il try that,at least now i got a rough idea what to look for.
,Also vulnax,are boost gauges accurate?the paricular one i installed was a tim,mechanical,(makers name)but i would imagine the innacuracy would not amount to 7psi?.just a thought!..
anyway thanks..
RDB..

Scott.T

iTrader: (2)

How can a boost gauge be fitted wrong on an MY00. There's a spare nipple on the inlet manifold, just pull the bung off and use that.

If he has tee'd into anyting else then he really is a numpty and you are probably just seeing actuator cracking pressure and not boost pressure.

Does the gauge read negative boost at idle ? If it reads 0 boost then it's the wrong side of the throttle butterfly. It should read approx -0.5 bar.

This Piccie may help :
The thick Blue Hose Vacum (behind the Alternator) goes to the Dumpvalve, under the coil packs.
The slightly thinner hose to the left of it, goes to the Boost Gauge. This Nipple is normally capped off with a rubber bung as standard.

RDB

Yes,I have seen that black bung,he as not connected the dump valve tubing to that,.......
Where.that red cap is in your pic,looks like spark plg cap?i have 2 black rubber tubes running roughly were your those 2 red rubber tubes are in your pic.hes put a t-connection into one of those,forgive my description,but im thinking from memory,lol,not very mechanicaly minded either.
yeah when car is idling it is running at minus 0.5...
so basicaly he did not need to put a t-piece in,he should have conected the pipe that came with boost gauge to that nipple?..what a damn idiot..and the best part is i was charged £105 for the garage to instal it...
I appreciate your Help thank you..
RDB...........

RDB

Dont think im mad,But i have had to go out with my torch,and look under the bonnet.i can see exactly what you mean now .all he had to do was damn well pull off that back bunge and connect the pipe from gage to it..good god.Im sure now i could have fitted it myself.lol