Ellow Harry.
There are 3 plenums sort of.. two small ones situated by the bonnet hinges, and one long very deep one in between those two..
The shallow ones are very easy to get at, and the one on the passenger side has a lil wall between it and the main one that stops any debris getting in from that side..
The shallow one on the driver side does not have a wall due to the wiper arm drive shafts being in the way, so leaves and other rubbish can get into the main plenham from that side thus blocking the drains in the bottom and causing water to slowly fill it up untill it both reaches the ECU and overflows via the pollen filter into the passenger side footwell..
Jules has designed a lil wall that goes in the drivers side to prevent any rubbish getting in from that side..
The wire mesh bit is to block a smaller hole that also lets rubbish into the main plenum box..
If you weren't confused before, you should be by now!
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