Tennis ball stuffed in the exhaust pipe will test the entire system. I don't listen for a hiss - I get a mustard bottle full of water and 10 drops of soap. It will foam when you find the leak. Just soak the hell out of everything and you will find it if it is a leak.

He as a point check for leaks that way.

It really sounds as if your wastegate valve.

If anyone is located near you run a second boost gauge off the turbo and to the wastegate, or straight into the gauge. See what boost the turbo is running off.

I am wondering if maybe you just have a bad turbo? The odds are against it but doesn't mean the the T-25 died and the GT25 was DOA.

How would a tennis ball in the exhaust pipe do anything different compared to what I've already done (ABS caps in the turbo inlet to the final elbow at the TB)? The IC pipes aren't broken. This is not a pinhole leak. If it were a pinhole leak or a tiny leak that were exasperated by pressure, the 30psi I fed the IC pipes today would have revealed it.

Can a turbo spin freely, have minimal shaft play, and still be bad?

Again, the wastegate is wired closed.

I thought you were looking to check the exhaust side for external leaks?

"I'm going to figure out a way to test the hotside piping"

Why would I care about an exhaust leak? That won't cause the turbo to suddenly stop making boost, would it?

Hotside = piping between the turbo compressor and the intercooler
coldside = piping between the intercooler and the throttle body

I'm going to give PR Motorsports a call on Monday. I'll let you all know what the cause of this was.

My bad - I thought by hotside you were meaning the turbo manifold (losing pressure before it hit the compressor). I've never heard that terminology before concerning turbos (only SC's where hotside refers to the exhaust side of the engine).

No problem. I'm pretty fucking irritated at this problem, so I'm a little on edge. If it was something obvious like a busted wastegate or a failed turbo, I'd be fine with it, but going through every single possible cause of this and still not knowing why is really frustrating.

I've been building this car for a year, and it's only been running for 6 weeks, and I leave for college in 3 weeks and the car fails? Fuck that. I want to drive the thing, not chase some bullshit ghost problem.

Not that it helps with your problem, but how did you wire the wastegate closed? Picture?

UGH, I meant turbine not compressor. Screw it, I'm going to bed...

Normally No if the turbo spins free and has minimal shaft play then normally the turbo is fine, but i think your problem goes pass normal. Maybe one of the interal seals on the turbo is shot and causing it not to build pressure but the bearings maybe fine.... again not a normal thing but I have heard of one turbo back in the DSM world that someone had that one of the seals was bad but the bearing was fine.

IF you know anyone around you with a working t-25, pull it from their car swap it to your and see if corrects the problem. Otherwise I am completely out of ideas man.

Good luck and please tells us what the cause is.

I'll shoot a picture when I load it up. Just some safety wire wrapped around the wastegate arm and the actuator bracket.

So, Andrew, what was the issue here?

Yeah! You have had almost eight years to figure it out:giggle:

Thread made by Andrew about something turbo. Must be ancient.

Andrew wiring GT2554r wastegate shut.

I like his style.

The divider that BEGi used to weld into their downpipes was holding the WG flap open, IIRC.

:rofl:

https://www.miataturbo.net/attachmen...ine=1397770602

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