gave this a go and wow, was amazed lol.
found this leaking out the inlet manifold.

took manifold off and cleaned the mating surfaces and put back together using instant gasket this time as well.
done smoke test again n looked tight

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cars idling alot more smoother now and vacuum goes straight down to around -20 In/Hg where it was around -5/-10 before. job done me hopes

Had the 17953/P1545/005445 - Throttle Valve Controller: Malfunction code for a bit but i assume thats because the throttle body was off, has since cleared.
Pics of Smoke Tester
Just an old metal coffee tin i found lying around, drilled 2 x 20mm holes and used CTS stuffing glands to secure the pipe that i had.


I just used the brake booster port to inject the smoke, sealed with tape

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Used a 12v compressor connected to the pipe with a valve thing made air tight.
I just lit some oily rags i had lying around and through them into the tin, worked a treat.
