Hi all, did a boost leak test at the turbo inlet earlier & found it leaks. After process of elimination i disconnected the intercooler & blocked it off at the turbo side so in theory just testing the turbo. Still leaked & found the wastegate actuator was leaking but also the air pressure was getting into the engine. The only thing I could think is its going down the oil flow & return pipes so would this mean my turbo is shot. It doesnt smoke has minimal shaft play & minImal oil in the inlet pipe. Reading online some say normal some say its not I cant see how it could be normal as surely that would add unwanted boost pressure in your crankcase/valve cover. Am I missing something or has this happened to anybody else TIA

 

The turbo seals are dynamic so pressurizing the turbo inlet will pressurize the CHRA and subsequently the block through the oil drain to the pan. To eliminate you can simply disconnect the turbo outlet coupler and test from there.

 

Hi, thanks for the reply thats re-assuring to know my turbo isn't shot. It's so confusing when you search online as most say do it from the turbo inlet.

When I do it at the throttle body so just to test the engine it also loses pressure & again comes out of the valve cover & I've tried turning the crankshaft as some suggest to close the valves & still can hear it hissing. I hear blowby is very common on the evos is that something I must have, if so should I do a compression test to check that. Thanks again

 

If you want to test the engine then you need a leak down tester. Pull the plug and put that cylinder on TDC compressions stroke then pump 100psi to the tester and measure the residual pressure. Not sure what you gain by pressurizing the TB.