To clean or not to clean .I usually power wash the car including underneath when I go for the NCT my thinking it shows a bit of respect to the person having to inspect it ,but Big Dommo recons if you clean it they can get a better look and find more faults like worn rubbers or boots ? So what do you recommend clean it or leave it ? Upside of a good clean for the NCT is its done for the Suitability a few days later !