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What happened was I blew the front ceramic wheel so I got another turbo replaced it then I rebuilt the first engine put it all back together and only making half boost so I assumed one turbo was working and the other was stuffed only found one wheel in exhaust the cat looked stuffed do I sold the engine pulled the turbos dropped new engine checked the wheels on both turbos they both spun free didn't look like blades where missing put it all back together and now no boost at all if the cat was blocked it would be quiet wouldn't it the only thing I've done is pulled intercooler to inspect and put it all back together a totally blocked cat wouldn't the exhaust glow red

Edited by Hot33r8723
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What happened was I blew the front ceramic wheel so I got another turbo replaced it then I rebuilt the first engine put it all back together and only making half boost so I assumed one turbo was working and the other was stuffed

it doesn't work like that - if one turbo is seized or has lost its turbine, then its compressor effectively makes a hole to atmosphere that the boost from the good turbo will flow out of.

Half boost is a boost control issue.

Just pulled of the pods and intAke pipe on the front turbo and started the car and it's not spinning do u think I lost a wheel if a engines compression was really low on all cylinders would it make boost still

Won't build any boost there is no vacum to wastegates at all there is vacum on my boost gauge

I dont understand how that can be - dont they both connect to the plenum? No vac to wastegates suggests a leak, and if you have a leak you wont make boost.

I dont understand how that can be - dont they both connect to the plenum? No vac to wastegates suggests a leak, and if you have a leak you wont make boost.

No. Wastegates get their signal from compressor outlet, not plenum. Plenum bad, compressor outlet good.

No. Wastegates get their signal from compressor outlet, not plenum. Plenum bad, compressor outlet good.

Given that they're connected - how much difference does it make? (assuming the intercooler flows well)

Any ideas on how OP gets nothing at actuators but vac at boost gauge? I would have assumed they would be pretty much the same at idle.

Guess what I reckon it is a blocked cat

If the cat is blocked, I highly doubt the car would even run. Try starting your car with a tennis ball in the back with duct tape.

ive seen a car drive perfectly ok with a blocked cat, but there was zero boost..

why would you need vacumn at the turbo actuator, it only needs to open under pressure, so what we have here are 2 turbo's which are supposedly ok... and highly likely a blocked shit cat. and zero boost.

If both turbo's flow there air/pressure into the intake, then you could test each turbo individually to check if they are making proper boost..that would save stripping it all down again..?? and replace cat obviously..

Edited by SliverS2

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