Downland grass, wooded commons and your cabin filter
Coulsdon has more open grassland on its doorstep than almost anywhere in London. Happy Valley Park and Farthing Downs are chalk grassland, and Coulsdon Common is a mix of grass and woodland. In early summer, grass pollen from those areas is carried across the town, and if your drive takes you along the lanes past them, your car's fresh-air intake is drawing it in the whole way. The worst months are usually May to July.
The cabin filter is the only thing stopping that pollen reaching the people inside. A new filter traps most of it; one that's been in since the last service may be close to saturated. Cars parked in Smitham and the roads around the commons also collect leaves and seeds on the scuttle below the windscreen, which can block the housing and drains. On damp autumn and winter mornings, a blocked filter means a windscreen that's slow to clear.
The driving itself adds to it. Most residential roads are now 20mph under Croydon's borough-wide scheme, and the A23 Farthing Way queues at the Lion Green Road junction at peak times, so local journeys are slow, with plenty of time spent behind other traffic. An activated carbon filter absorbs some of the exhaust smell in those queues and is worth considering if you commute up the A23 towards Purley or down towards the M25.
When you bring the car in, we remove the old filter and show it to you, clear any leaves from the housing, check for damp and fit the new filter the right way round. From the town centre take Smitham Downs Road to the A237 and head north through Wallington, about 17 minutes. Most people have it done with a service, but it's quick enough to wait for. If the car also needs a service, we'll check the filter's condition then. There's a written quote first and a 3-month workmanship warranty.