I have a 99 4Runner with the TRD Supercharger, I just had a shop install an Autometer boost gauge. When I picked it up they said that they were only getting 2-3 psi of boost and that I may just need to service the supercharger. Well when I drove it home I was only getting vacuum, no boost. At idle I was showing around 17 psi vacuum, just cruising I would get about 10 psi and when I really got on the gas it would only hit "0". I am guessing they hooked it up wrong, can somebody tell from the picture below if they hooked into the wrong line?
Thanks!

 

Here is a video, maybe it will be a little more clear exactly which line he used:

http://s101.beta.photobucket.com/use...7b2de.mp4.html

 

as long as the hose is hooked into the intake manifold in a spot that is unaffected by the throttle position it should be fine. You could try changing the vac tube location to another point and see if that changes your numbers.

Engine vacuum is counted in inches of mercury, not psi. Boost is calculated in psi. Pulling 17 inches at idle sounds about right as does 10 inches while cruising.

Hopefully someone with the same setup can chime in. Changing the thread title (if possible) to something with "3.4 supercharger" in it will bring in the people you need.

 

sounds like you either have boost leak, or the boost gauge leaks.

 

If the boost gauge was leaking would I still be getting normal vacuum readings?

The truck has 182,xxx miles on it, I only bought it a couple months ago so I am not sure when the supercharger was installed so I should probably just go ahead and replace the nose drive, but dang the kit is $550!

 

Hey now slow down a bit!!!! might verify everything possible before you start talking rebuild kits, let the answers come in and see what is figured out!! I highly doubt the charger was installed off the factory line so I wouldn't imagine it has that many miles on it. Do you have any ties with the PO to fine out some history??

 

Hello to a fellow Mile Higher!

Unfortunately, I do not know the previous owner, I bought it through a dealership (Kuni Lexus)

 

Oh dang didn't even notice the location Hmm wonder if there is a way to test the gauge to see if its functional? You got a mechanic you can go to? I would imagine you could test it with another testing gauge to compare the readings??

 

That is probably what I am going to have to do, but just don't want to have to drop more cash if it turns out the shop simply installed it improperly.

 

reading vacuum is small negative pressure. But if its got a poor connection under boost it could be leaking. However these first gen sc units were prone to leaks around the idle bypass valve.

 

where does the line run to? it doesn't show in the picture and I have a black second gen sc.

 

I'm not sure exactly where it goes, the video in my second post kind of shows the line a bit better.

 

Looked at the video, the source is okay. What else is pigtailed into that line? do you have any fuel mods on the rig?

 

i have the black s/c and it has an allen head set screw type of deal on the back on the s/c.. remove that and install brass fitting that came with the boost gauge. feel around for a spot on the back.. its looks wrong with all thoes T's.

some info here http://www.gadgetonline.com/Super.htm

 

Just a thought, maybe Kuni might run the Vin # and at least give you any maintenance/warranty history. It might have some info that could help.

 

Just my $0.02, but it looks as if they might have just tapped into a vacuum line.

I just ran it past our MDT here at work. He thinks they tapped into a vacuum line to, especially if vacuums all your reading. I've seen guys tap into this port here to read boost before.

 

Sorry about the delayed response, been out of town with no internet access.

Hmmmm, I talked to the shop and they insisted it was done correctly, they were actually kind of jerks about it.... I see you are in Colorado, know of any good shops that can take a look at it?

 

I'm really not sure what else is pigtailed into the line, I will try to take another look tomorrow. I do not know of any fuel mods installed, I've only had it for a few months.

Any Colorado peeps recommend a great shop that knows their stuff that I can take it to? I feel like that is probably the best thing to do at this point.

 

Where do you live at, the guy I go to is wondrous and the guys he knows across the way are all turbo fiends.

 

I am in Parker