Go and Check Your Tyre Pressures

Over the last few weeks it has gradually got colder and my car's economy has deteriorated significantly. Much more than last year..

I decided to check the tyre pressures today.  The TPMS system showed 3 wheels at 32 psi (2.21 bar) and one at 31 psi (2.14 bar). The car's manual specifies 36 psi (2.48 bar) but I usually blow my tyres to 38 psi (2.62 bar). It helps economy.

TPMS is clearly a safety device - but in my recent cars is only effective if just one or perhaps 2 tyres are well below the pressure in the other tyres. If all tyres lose pressure at a similar rate - even when they reach 4 psi (0.28 bar) lower than the recommended pressure - no alarm is shown.

Now that I have corrected my poor diligence and blown the tyres up to my normal setting - it will be interesting to see whether it has much effect on economy.