Boost gauge plumbing - advice
 

Ok so this may be a little long winded - sorry in advance.

Originally my Boost gauge was Plumbed in just off the manifold - it would read below 0 say around minus 15/20 or there abouts when the car was just idling.
When getting the car mapped the boost gauge was showing different figures to what it was showing on the computer, so I spoke to a subaru specialist and he said they normally run the boost gauges off of the turbo actuator.

So I left the car off to get them to do it to make sure it was done right, I've got the car back now and instead of it rearing say minus 15/20 or what ever it was it reads 'slightly' below 0, probably in the region of minus 2/3.

Now this happened before when it was originally plumbed to the manifold and a hose popped off.

Really I'm just wanting to know, is this normal for when the gauge is plumbed off the acutaor? Maybe this will solve the incorrect boost readings up top.

Thanks, Matthew.

https://content.subarunet.com/snet/b...50-US7_alt.pdf

subaru recons piping off the dumpvalve vac line is the way to go - that's where mine is and it sees similar readings to your first install (strong vacume it idle, strong boost later on).

I believe your original one was tapped in here:
http://img809.imageshack.us/img809/5...ostgauge02.jpg
before it tried to escape on you. It could have been pressure coming from the other side of that pipe (i think it's the EGR solenoid?) causing your false reading on the boost gauge.

I guess if your now connected to the turbo nipple then you don't have the engine vacume working for you so it's only really going to see the positive boost from the turbo.

Which is fine if you want to know about boost, sometimes it's good to know about vacume as well.

Most of mine have been t'd off the vac line on the OEM recirc valve and hidden under the intercooler ;)

I've ordered some more hose so I can fit it to the dumpvalve vacline :).
It's definatly showing the wrong readings at the moment. think it's about 5/10 psi off lol

My Defi is taken straight off my car's manifold, via an unused nipple.
It reads to within 0.05 bar.

remember it is supposed to read a little different to manifold pressure though if your reading it at the turbo nipple - the intercooler causes a change in pressure.

Surely it shouldn't be like 10PSI off lol

hah - no i wouldn't think it should be that far off, maybe like 3psi or so.