SR20 Exhaust Leak Boost Issue?

[tsahlin489]

Forgive me for not introducing myself prior to this posting, however I am in need of an answer fairly quickly.

I have recently encountered quite a large crack and hole in the my exhaust, and I am at a loss of whether that is the reasoning for my hindered performance. Up until recently my car would spool to 8psi quickly and consistently, however that is no longer the case. About a day after I discovered the crack (God knows how long it was actually there for), my car began to decline quite a bit. When opening the throttle up, the car just BARELY clears 0psi, and that is when it is cool out. Once the car (or outside temps) warm up the car won't even clear -10Vac.

I have checked all my vacuum lines and have found absolutely nothing that looks out of place.

Is it a coincidence that both of these issues seemed to arise at the same time, or could my loss of power be directly related to my exhaust leak? This was an overnight occurrence as well, might I add. Monday night she pulled hard as ever then Tuesday morning I could barely make it up to highway speeds.

Any help would be greatly appreciated, and I can post pictures upon request

[tsahlin489]

A picture of the cracks in the exhaust. This is in the mid-pipe, right up near the cat :bite:

[rcdad123]

unbolt the cat and go for a drive. if it runs strong again, then the cat is clogged. if it does not make any difference, check for boost leak or vacuum leak. you mentioned -10 vac. it should be around 18 or higher. low vacuum means you have a leak in the intake manifold some where.

[MrSanchez925]

make a boost leak tester and test the system.

that will tell you right away.

[tsahlin489]

unbolt the cat and go for a drive. if it runs strong again, then the cat is clogged. if it does not make any difference, check for boost leak or vacuum leak. you mentioned -10 vac. it should be around 18 or higher. low vacuum means you have a leak in the intake manifold some where.

make a boost leak tester and test the system.

that will tell you right away.

So the crack in the exhaust really isn't related to my loss of power and response?
What is the most efficient way to check for a boost or vacuum leak?

[MrSanchez925]

a crack in the exhaust can hinder performance do to having an exhaust leak.

But it wouldn't cause your symptoms.


Now your cat may be clogged but that would cause all sorts of issues as well more then what you are experiencing.

You may have a stuck WG or numerous leaks. from all sorts of places.

the most efficient way is the way I just said.

make or buy a boost leak tester.

its fairly simple to make one.. just google it.

[tsahlin489]

a crack in the exhaust can hinder performance do to having an exhaust leak.

But it wouldn't cause your symptoms.


Now your cat may be clogged but that would cause all sorts of issues as well more then what you are experiencing.

You may have a stuck WG or numerous leaks. from all sorts of places.

the most efficient way is the way I just said.

make or buy a boost leak tester.

its fairly simple to make one.. just google it.

Thanks man, hopefully I can detect the problem quickly. I won't be able to mess with anything tomorrow with work however Saturday will be devoted to getting her up to par again. I'll let you know the outcome