Engine Dressings

Use a water-based dressing rather than a solvent-based one. Suitable options include CarPro PERL and Autoglym Vinyl and Rubber Care. Water-based dressings are safe on rubber hoses, plastic covers, and engine bay trim, and they do not produce the greasy film that attracts dust over time. Apply to plastics, hoses, and rubber surfaces only after cleaning the bay and allowing it to dry fully.

Yes. Disconnect the battery before applying any chemistry. Cover or bung the air intake and alternator if they are exposed. Pre-rinse at reduced pressure to remove loose grit, then apply a dilutable APC degreaser such as Koch Chemie Green Star or Bilt Hamber Surfex HD, agitate with a soft brush on delicate plastic and electronics areas, then rinse at reduced pressure again. Only apply dressing once the bay is clean and dry. High-pressure jetting directly at electronics is the main failure mode to avoid.

Yes. Vacuum the underside of the bonnet and the bay itself first using a brush-head attachment. Then use a rinseless wash solution (such as Garage Therapy Rinseless at 1:64) in a spray bottle, wiping down large areas with a microfibre towel and using detailing brushes for intricate areas. Apply a diluted water-based trim dressing (such as Garage Therapy Trim at 1:9) to engine bay plastics for a subtle finish. This waterless approach suits cars with light dust or sand build-up and takes around 20 minutes.