[How to] Install an aftermarket boost gauge

Write ups and tutorials for maintenance and modifications.

Re: [How to] Install an aftermarket boost gauge

Postby freddie » Tue Jan 24, 2012 4:07 am

I have a stock '88 ST165 and the same boost gauge as shown in your picture. It was fitted by the previous owner.
The nylon vac hose is connected to the brass tit in the end of the intake manifold next to the vac hose connection for the VSV etc.

On full throttle/power the gauge only reads about 3psi (that is two didget marks before the 5 on the top scale).

Now the gauge is either hooked up wrongly or I have a problem with the turbo system.

The turbo is fine with no damage to the impellers and no play in the shaft and the engine is healthy. The TWG is operating ok with in the factory specs. That leaves the turbocharging pressure VSV or the T - VIS VSV or turbocharging pressure sensor to be the problem. No I don't have any vacuum leaks.

The questions I ask here is (please) are:
Is the gauge hooked up correctly?
How can I test these bits (VSV T_VSV etc, etc,)?
Better still how do I get around the TCP VSV and sensor and hook up a manual controller?

I would like to raise the Turbo Pressure to about 10psi. No more than that I think, as the motor is original and has done 160k's (until a couple of weeks ago had the original factory Denso spark plugs were still fitted)
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Re: [How to] Install an aftermarket boost gauge

Postby WarTowels » Wed Jan 25, 2012 7:25 pm

Same gauge as the original poster? - "shown in your picture" - (This thread is 5+ years old, the OP isn't even active any longer. lol.)

Anyway, what you haven't said is, what does the gauge read when the car is on, idling?

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Re: [How to] Install an aftermarket boost gauge

Postby Awesome-Trac » Sun Dec 07, 2014 6:44 pm

ive recently added a aftermarket boost gauge, now im wondering if i pick up a 87 gauge cluster with the voltmeter instead will it be hard to hookup? so i can get rid of the old oem one
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Postby Rallly » Wed Oct 07, 2015 10:41 pm

Gary wrote:
snakeeater wrote:Could I T It before That white filter thing or one the line next to it?? Would I get as accurate readings compared to if i Used the "proper" port??

Yes, you will get the same reading.
That plastic thingy is a "jet" or one way valve.
If you connect the gauge to the line before it, you will read both vacuum and boost correctly.

Where do you mean "before it"?
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