remove all the breather pipes and check they are clear,
also check the large lower pipe entry into the block as that builds up with carbon
there is also a vent plate bolted to the underside of the inlet cam cover the ways within block, this is only accessible by removing the cam cover then its screwed to the lid where the pipes exit
the black PCV valve is not a one way valve
what it does is regulates the vacuum onto the head/block which regulates the positive pressure within the block
https://en.wikipedia.org/wiki/Crankcase_...ion_system
also check the large lower pipe entry into the block as that builds up with carbon
there is also a vent plate bolted to the underside of the inlet cam cover the ways within block, this is only accessible by removing the cam cover then its screwed to the lid where the pipes exit
the black PCV valve is not a one way valve
what it does is regulates the vacuum onto the head/block which regulates the positive pressure within the block
https://en.wikipedia.org/wiki/Crankcase_...ion_system
https://www.check-mot.service.gov.uk/
GTI6 Info
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