Hiya

I've got a boost gauge on my MY06 WRX, most of the time it is showing a negative reading and only when the turbo is really spinning (4000rpm upwards) does it show a positive value. I would have thought that as soon as the turbo is spinning that it would read +ve Boost.

Could there be a leak in the hose between the gauge and the engine, (plumbed into the vacume hose on the DV) or could there be a problem with the gauge itself.

Any thoughts appreaciated!

Thanks

 

I think you have it fitted to the wrong place. Should be teed into the pipe which comes from the manifold just behind the alternator or fitted to the spare take off on the manifold in the same place.

 

I used some instructions that were on here previously, a few people did mention a pipe on the manifold but its not on the 06 model as far as I'm aware, do you have a pics ata ll.

Thanks

 

Mine is plumbed into the DV pipe and has been for the past 2 years with no problems (Classic 93 WRX).

Is the gauge accurate?

HTH MY 93

 

It's working just fine. That's what is supposed to happen.

The boost gauge is showing the air pressure inside the inlet manifold. Depending on how much throttle you are using. Bellow ~3000rpm you will see readings between - 0.7 Bar and zero (the turbo can't produce boost at these revs). And above ~3000rpm you will see anything between - 0.7 Bar (no throttle) and + 1.2 Bar (Full throttle, for example, will depend on what max boost your car is set for).

 

Cheers Normski, thats makes a bit of sense now, I can get it as +ve boost but have to be really moving, the gauge is in PSI so normal town driving it flaps between -30 and 0.

Thanks
Arron

 

You get a negative reading when your foots not on the pedal thats normal, once you accelerate the readings should start to rise and won't show a 0+ reading until the turbo actually has positive boost! i.e. as you stated "when the turbo is really spinning"

Test by planting it and it should reach maximum boost and stay there till you come off the accelerator, then it should drop -0 maybe all the way to -30 if your gauge reads that low, if this happens its fine. At 4000rpm depending in what gear etc its normal for you to only just be hitting 0+

But if in 1st you're reving the nuts off it and not getting any + boost then you have problems.

when you swtich off you engine the guage should read 0 (or just sit under)

 

A friend of mine's scooby is the same'ish!

when getting a 0 or slightly neg reading on the gauge you can still here a small dump????? (which surely has to be positive pressure)......changed for another gauge and still reading exactly the same!

thoughts?

 

You're having a laugh if you think it's normal to only get +boost above 4k..!

My 05 WRX hits peak (1.45bar) at 3200 rpm with 1 bar at ~2900 rpm..! This is with a VF35 BTW, the standard TD04 should be hitting 1 bar/14.7psi at around 2500 with peak (~1.1bar/16 psi) by 2900rpm even with cats inplace..!

I've got a pic somewhere of the correct connection, as to me you've either connected in the wrong place or there's a problem with your scoob..!


Edited to add pic:

http://i14.photobucket.com/albums/a3...connection.jpg

 

Any chance of a better pic as the bottom half seems to be missing ?

 

Doesn't it connect like this ?

Boost Gauge Fitting

Seems to be two ways to fit it - Does anyone know which one is correct for definite ?

 

Scoobypedia | Trusted knowledge for everything Subaru | Boost Gauge browse

This one. Read it through, there is a part you need to reverse..

 

Thats the same link i posted above

So that is the correct way then.

 

Quote from link:

"Note that in the picture above the strange device (dump valve signal hose) is turned around 180 degrees. You will find it facing the other way."

Did you do this?

 

No i am fine with that the question is that others are saying to fit it somewhere else altogether different .. Like this....

http://i14.photobucket.com/albums/a3...connection.jpg


So the question was which one is correct.

 

and where do I get the T piece to fit it like this ...

http://i14.photobucket.com/albums/a3...connection.jpg

Looked at LMA but can't see a 6mm >3mm T piece, and I think the OE dump valve hose is 6mm, not 5 ?

 

So nobody knows the definitive answer on where to fit a boost gauge ?

 

Arronb,

Mine behaves as yours does. My dealer's performance person said if I want boost earlier to have my ECU remapped... PPP. A very reputable Subie builder told me the same thing. My subie is a stock 05 US WRX.

Mike

 

so i guess for all others searching for the ideal place to "plumb" your boost gauge in - The answer is two ways as shown above in this thread

 

MY01 WRX
I fitted my lamco on the dump valve vacuum pipe as shown here

http://i14.photobucket.com/albums/a3...connection.jpg

It works fine now that I've got everything sealed tightly. My first fit whilst I drove to the shop of a proper T had a slight leak and it was noticable due to low gauge reading, bouncy gauge needle, car felt sluggish on boost and I could hear the air compressing back onto the turbo when I lifted off as the dump valve wasn't opening as it should (kewl chirpy noise ).

Now with standard TD04 and decat it hits 1bar at around 2,500 and then the 1.3ish it's mapped for as I floor it after that. At around 5000+ is starts to tail off slowly down to 1bar near rev limit. Needle does have a little 'judder' sometimes when not on full boost and I'll pop a restrictor in the line to try smooth this out. On idle or on overrun it will drop down to -30 or sometimes below when pottering around at 30 in 4th. So it seems that position of fitting works fine.

 

Note to self - sometimes a DB error page means everything has actually worked

 

I am sorry could you repeat that

 

by the description of the issues you are having sounds like i shall fit mine in the other position as Subaru suggest.