My Skoda Superb Mk3’s steering feels light when I first start the car, but after driving continuously for about 15–20 minutes, it becomes noticeably tighter, even at low speeds. If I switch off the car for 20–30 minutes and then restart it, the steering feels light again. I replaced the battery and alternator about six months ago, but this issue has recently started. Is anyone else experiencing the same problem?

Hello, welcome to the forum.

That sounds as if you may have a fault with your steering rack or the variable-rate control to it - strongly suggest getting the steering inspected ASAP.

The suspected fault will not leave you without any steering at all if the assistance fails completely - but it may well feel like it!

Agree with that - get someone to look at it. Slower speed steering will feel heavier naturally so that stacks up.

54 minutes ago, travs said:

Agree with that - get someone to look at it. Slower speed steering will feel heavier naturally so that stacks up.

But sometime it feel lighter at slower speed. Car V belt and tensioner worn out. Will this can be the reason?

If your Aux. belt and tensioner are inhibiting correct battery charging - or are allowing battery voltage to drop too low, this could affect the electro-mechanical power steering - but this would also adversely affect starter motor operation, which you do not mention.

15 hours ago, Warrior193 said:

If your Aux. belt and tensioner are inhibiting correct battery charging - or are allowing battery voltage to drop too low, this could affect the electro-mechanical power steering - but this would also adversely affect starter motor operation, which you do not mention.

Their is no issue with starting the engine

Suggest addressing the Aux. belt and tensioner issue and see if that could be the cause.

Does your automatic stop/start operate correctly?

Have you checked the battery voltage?

Just a thought - do you have Lane Assist active on your car?

Are you experiencing the heavy steering after lots of turning at very low speeds? The power steering could be reducing assistance to prevent overheating in this case.

12 hours ago, Warrior193 said:

Suggest addressing the Aux. belt and tensioner issue and see if that could be the cause.

Does your automatic stop/start operate correctly?

Have you checked the battery voltage?

Checked the battery voltage and it shows 13.5 volt after start the car and around 12 when the car is turned off.

12 hours ago, D402 said:

Are you experiencing the heavy steering after lots of turning at very low speeds? The power steering could be reducing assistance to prevent overheating in this case.

Nope. I am using steering normally without lots of turning

Your charging (engine running) voltage may be a little low and the voltage with the engine off indicates a SOC of around 50% if all control modules were in sleep mode when that reading was taken.

With your battery at around 50%, I would expect a charging voltage above 14 volts.

This may be part of your problem.

Can you measure the battery voltage when you are actually suffering from the heavy steering to see if it drops under load from the power steering? The power steering should be fully functional even at 12 V.