Turbo Gauge Not showing as much boost

[redmkiii]

Its right next to the cruise control, here is the pic, it is that little black box, http://www.supramania.com/forums/attachment.php?attachmentid=57&d=1112757962

 

[Studduck]

Its right next to the cruise control, here is the pic, it is that little black box, http://www.supramania.com/forums/attachment.php?attachmentid=57&d=1112757962

it says I dont have access to that page

 

[swaq]

Make sure you're logged into SupraMania before clicking the link.

 

[starscream5000]

It's on the drivers side fender well, behind the strut. It's a little black box that should have a metalic sticker on one side saying something like, "turbo pressure sensor". The vacume line is on the bottom of it, you can't see it, you must feel for it.

 

[Studduck]

So this is where I am at with the leak:

I have checked intake, BOV, ic pipes, and vaccum lines.

I can hear the turbo, and it sounds fine. The gauge doesnt show any boost until almost 5000 rmp in first gear. I can get it almost to full boost in 5th gear (at 60+ mph). I'm almost positive its not the gauge, because I don't feel the boost until it is shown on the gauge. (i can hear it though). Engine sounds and runs great. I'm having no other problems besides the boost. What should I check now?

 

[starscream5000]

Have you checked ALL vacume lines, including the hard to reach ones under the manifold?

 

[Studduck]

When I blow air into the IC pipes I can hear air leak from a certain area. It behind the alternator, near the oil cap. We plugged up all pipes going back into the accordian pipe. Where is this air leak comming from? Is this a leak or just normal air entering the engine?

 

[starscream5000]

Maybe it's the hose coming off the valve cover right under the oil cap?

 

[trydrew]

Thats an oil line star.
Maybe you have an iac valve that leaks? I dont know if that is possible though. Maybe its a leak between the upper and lower manifolds? You need to do a little more investigation, I think.
Oh yeah, is it running rich?

 

[Studduck]

Well I do smell gasoline at times, not too often, but when I am outside the car and it is running I smell gasoline.

 

[starscream5000]

Did you take your Charcoal can off? Or is the pic you posted a recent one?

 

[3p141592654]

Remove the ISC and pull out the check valve behind it. Make sure the valve is clean and not torn. You will want to have an ISC gasket on hand when you put it back together.

 

[trydrew]

Remove the ISC and pull out the check valve behind it. Make sure the valve is clean and not torn. You will want to have an ISC gasket on hand when you put it back together.

lol Now why didnt I think of that...
Yes there is a diaphram in the check valve that only allows air flow one way, so that it doesnt leak under boost.

 

[Studduck]

could a slipping clutch lead to a lack of boost?

 

[trydrew]

could a slipping clutch lead to a lack of boost?

If the car is still drivable, I would say no. Did you check the ISC yet?

 

[Studduck]

where might I get an ISC gasket at? do I need a new one if Im just taking a look at the valve?

 

[trydrew]

where might I get an ISC gasket at? do I need a new one if Im just taking a look at the valve?

Yes. You could go to Toyota to get one, but you could just use a cut-your-own-gasket sheet.

 

[Studduck]

Yes. You could go to Toyota to get one, but you could just use a cut-your-own-gasket sheet.

the gasket I have right now is metal, is that best?