Mark the stuff you are looking at sounds like CLAD (the fungus) I see toyota is selling cans of anti fungus stuff.
I fitted the water probe to the Raycor filter today...very very easy to do. took about 15-20 mins at most. I fitted the orange LED to one of the blank switch covers near the cig lighter...Cost was $138.00 inc..
Even got the wife and oldest boy out to the car and made them look at the light...told the wife to stop straight away if it comes on....the lad is only 4 but I think he will notice it before the wife will
I got home the other day to find the lux with only enough fuel to get me 3kms according to the computer.. filled it up and it had 5 lts left in the tank..I went off my nut
:x
But I checked the filter bowl and there was NO gunk in it ...but I am sure the lux's fuel gauge will not see the wrong side of a 1/4 tank ever again