Thanks for all your answers! You were right, it was the wheels. They were balanced in November, but either something went wrong or the wheels have radial runout. I've now fitted my Cetus rims and the vibrations on the highway have disappeared. However, the ATF doesn't look clear red, so I ordered an...

Hello everyone, thanks again for all the tips. After experiencing increasing start-up problems in wet weather/humidity and ruling out the fuel supply as the source of the problem, I replaced the entire ignition system (spark plugs, ignition cables, distributor cap, distributor finger). The car now s...