Why do my tyre pressures keep dropping?

I am losing pressure from three of the tyres on my Ford Fiesta 2014. I left the car unused for four weeks and the tyres reduced from 30PSI to about 20PSI on three tyres. Two of the tyres were fitted about six months ago including new valves.

Asked on 14 October 2019 by robjudi

Answered by Honest John
It's one of four things: Slow punctures in all three tyres (unlikely); faults with the valves; damaged rim seals or cracks in the alloy wheels allowing loss of pressure. Start with having the tyres re-sealed. If you're still having trouble, replace the valves.
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