those of you with the stock boost gauge i have a couple of questions for you:

what does your gauge read when you're cruising down the highway with your foot not on the petal much?

what does your gauge read when you're in 3-5th gear around 4k rpms with the throttle 1/2 way open?

what does your gauge read when you're totally flooring it?

i just had the dealer install the options for my 05 STi monday and they installed the stock boost gauge along with a few other options. i think they managed to botch the install since until yesterday i was only able to get the car boost gauge to go up to .05MPa (~7.25psi) i was on the highway and i was really flooring it at high RPMs and i was able to get it to around .09MPa (~13.5-14psi) which is closer to what the full boost should be. however when i'm cruising down the highway the gauge shows a vacuum of -.07MPa which seems low. i read in some other posts/forums that when cruising the gauge should be maybe -.01MPa to -.02MPa. the gauge also sounds like a blow off valve (i get a nice little "ssssssssss" sound from the gauge when i shift and the car is making boost) when i shift so i think either the line running to the gauge or the gauge has a leak. (the dealer also might have calibrated the gauge wrong as well.) i called the dealer and i am going to take it in soon to have them play with it. (i was going to drop it off this morning but the dealer is an hour or so away and we had a few inches of snow + people who can't drive in snow so i'll take it in next week.)

in my full paranoia state i began to think what if something is wrong with my turbo and i'm only generating 1/2 of the boost i should be. hopefully this is just my extreme paranoia and it's just the gauge is messed up. the car feels like a 300hp car so i'm pretty sure the boost is proper, the gauge is just wrong.

anyways any input from you guys on the numbers you see from your gauge would be appriciated. when i test drove an 04 wrx i remembered seeing the guage hit .1MPa easily at only 1/2 throttle around 4k rpms. i know the engine/turbo/etc is a little different set up but the numbers should be somewhat similiar i would think.

 

I hate the stock boost gauge, its sooo worthless...

 

My stock boost gauge used to make a fluttering sound when I was close to full boost. I found out that I needed to install a vacuum restrictor in the hose in between the "T" fitting and the gauge. The restrictor prevents the turbulent air from the by pass valve making strange noises with the gauge. I got the restrictor from Kragen auto parts for a couple bucks. It is a small plastic piece with a brass restrictor inside it. The restrictor opening is only a couple milimeters wide.

 

I agree with Group B. The guage just hangs around unless your in the throttle then it boost to about half a bar. On occasion it gets off it's *** for a minute and hits full boost but I so rarely see that. I want to get the Defi gauges in the Gruppe S carbon fiber housing. Anyone have any experience with those?

 

mbquarts -- thanks for the info. i'm taking it back to the dealer to let them look at it and fix the leak/install a restrictor since a friend who has a turbo'd mustang spoke of something similiar with the gauge in his car.

 

bump.

can anyone who has the stock boost gauge *please* let me know what your gauge reads when:

1. you're cruising down the highway with your foot not on the petal much?

2. you're in 3-5th gear around 4k rpms with the throttle 1/2 way open?

3. when you're totally flooring it?

i'm just trying to figure out if my gauge is fubar'd or if the levels it's at (see the 1st post for more info) are normal before i take off a day or work to go to the dealer where i bought my car and the options from and get them to 'fix' it.

 

1. you should be under vacuum at this point, so something in the negative numbers

2. slight positive boost reading I would think

3. should read .11 whatever the silly scale that gauge has, I ripped mine out the night I got my STi home