# 84 Nissan turbo boost problem



## s13 hatch (Aug 10, 2007)

everything is basically stock and when i rev it up high it doesnt seem to have boost the boost gauge goes to -7 to 0 and doesnt go past zero. I think its a boost leak but what else could it be any help or suggestions would be very greatful


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## AZ-ZBum (Nov 21, 2004)

You won't get any real boost just sitting there. You have to be under load. Like, while accelerating. If you're moving and trying to boost, chances are you have a major intake leak.


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## Zen31ZR (Mar 24, 2004)

It depends on the wastegate and the boost controller. The wastegate spends most of its time at least partway open with stock turbos. The wastegate opens slowly the whole time boost is coming up, which in turn causes boost to build more slowly. The only way to get around this is to use an electronic boost controller, which has direct and immediate control over the wastgate. I've seen turbos at the drag strip building 15+ psi with no load on the engine. But it's common to not see more than 0 psi boost when revving up a stock turbo engine. And if you are referencing the stock boost guage, its pretty worthless. Buy a proper boost guage. Figure the stock guage is 20+ years old and has been vibrating around in the dash that long. Accuracy went out the window probably about 5 years after it was built, and the stock guage was only for looks anyway. Its about as worthwhile as the stock G-meter.


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## s13 hatch (Aug 10, 2007)

AZ-ZBum said:


> You won't get any real boost just sitting there. You have to be under load. Like, while accelerating. If you're moving and trying to boost, chances are you have a major intake leak.


so how do you know if the turbo is bad, so if the boost gauge is working and going up to zero that means its good?


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## s13 hatch (Aug 10, 2007)

Zen31ZR said:


> It depends on the wastegate and the boost controller. The wastegate spends most of its time at least partway open with stock turbos. The wastegate opens slowly the whole time boost is coming up, which in turn causes boost to build more slowly. The only way to get around this is to use an electronic boost controller, which has direct and immediate control over the wastgate. I've seen turbos at the drag strip building 15+ psi with no load on the engine. But it's common to not see more than 0 psi boost when revving up a stock turbo engine. And if you are referencing the stock boost guage, its pretty worthless. Buy a proper boost guage. Figure the stock guage is 20+ years old and has been vibrating around in the dash that long. Accuracy went out the window probably about 5 years after it was built, and the stock guage was only for looks anyway. Its about as worthwhile as the stock G-meter.


so how you know if the turbo is bad, if it goes up from -7 to 0 does that mean the turbo is still good?


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## Zen31ZR (Mar 24, 2004)

Drive it. What does the boost guage go up to when you are in gear and rolling. You should see between 5-7 psi after 3000 rpm if that guage is anywhere near accurate. If it still comes up to zero and stops, I would be inclined to suspect the guage first. Turbo failures are generally accompanied by a bit of smoke and maybe a rattling sound from the turbo housing. At least thats how it was with the one '84 that I saw with a blown turbo.


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