Short answer
Those marks on your paintwork are not dirt. They are limescale from your own tap water, left behind on the spot where a drop sat and dried.
That is why scrubbing harder does nothing, and why another bucket of water does nothing either. What does work: getting the water off before it has the chance to dry. It comes down to the order you work in, and to a towel that holds enough water to do the whole car in one go.
Why your car ends up covered in marks when you have only just washed it
Water evaporates. Everything that was in it stays behind, in the exact shape of the drop.
Tap water carries limescale, and in a hard water area it carries a lot of it. While the water is still sitting on your paintwork you see none of it. The moment it dries, only the water goes. The lime stays behind as a faint round mark. On a black car you spot it straight away; on a light colour you only see it once the sun catches the panel.
And that is where the usual habits start making things worse instead of better.
| What people do | What it does | What you are left with |
|---|---|---|
| Washing in full sun | The water dries faster than you can dry it off | The limescale is set before you even reach that panel. This is the most common mistake of the lot. |
| Washing-up liquid in the bucket | Strips grease hard | It takes the wax off your paintwork as well. After that water clings even better, so you get more marks, not fewer. |
| Vinegar on the marks | Dissolves limescale, but it is an acid | Not on paintwork, rubber or chrome. Whatever dissolves lime attacks what sits around it too. |
| Hosing it down once more | Dilutes nothing | You lay a fresh coat of hard water over the top. Drying twice means marks twice. |
| Taking the water straight off | Nothing is left standing to dry on | No marks, because there is nothing left that can dry in. That is the whole story. |
It is also why the question “should you towel dry your car after washing” has a straight answer: yes. Leave it to drip dry and every drop dries in on its own spot, and you are left with limescale rings that were not there before.
Never take a cloth to a dry, dusty car. The grit sitting on your paintwork is harder than the paint itself. Rinse first, so the dirt is loosened and washed away, and only then reach for your towel.
Never use fabric softener when you wash your cloths. It leaves a coating around the fibre, and after that the cloth stops taking up water. It is the most common reason a good cloth suddenly starts leaving streaks.
How to wash a car without streaks, in four steps
Four steps, and the order matters more than the technique.
Work in the shade, or early in the morning. Warm paintwork dries itself before you get there.
Rinse off thoroughly with plenty of water, so there is no soap and no grit left on the panel.
Lay the towel flat on the panel and draw it towards you. No polishing, no scrubbing. The towel lifts the water; you do not need to press.
Start at the top and work down. Windows and sills last, with a clean side of the towel. Car windows streak the moment you go over them with a side that is already soaked.
Wring the towel out as soon as it starts to feel saturated. A towel that is full moves water about instead of taking it up, and then you get the very streaks you were trying to avoid.
Are microfibre cloths safe for cars, or do they scratch the paint?
The cloth is not the problem. What is caught in the cloth is.
This is the question that stops most people, and the honest answer has two halves. A clean microfibre cloth is softer than your clearcoat and will not mark it. The risk was never the fibre itself; it is what the fibre is carrying. A cloth that has been on the ground, or that you used on the alloy wheels last week, holds grit and brake dust between the fibres. Those particles are harder than the clearcoat, and as you wipe you drag them across the paint under your own hand. That is where fine swirls come from, with any cloth, of any make. So the honest answer to “is it safe to use a microfibre cloth on car paint” is this: yes, as long as the cloth is clean and the car has been rinsed first. Get either of those two wrong and the softest cloth in the world will still leave its mark.
- 1
Keep your car cloths apart. Never the same cloth for the alloy wheels and the bonnet. Wheels collect brake dust, and brake dust is sharp.
- 2
If the cloth lands on the ground, it goes in the wash. Do not shake it out and carry on, however tempting that is.
- 3
Wash at 40 degrees, with no fabric softener and no liquid detergent, pods or capsules. Washing powder, or a splash of vinegar in the softener drawer, and the fibre keeps doing what it is meant to do.
- 4
Never in the tumble dryer. Heat damages the fibre, and a damaged fibre takes up less water.
What really counts in a drying towel
Not how soft it feels, but how much water goes in before it is full.
A car has a lot of surface. If your towel is saturated by the time you have finished the bonnet, you are spreading water over the rest of it rather than lifting it off. That is why capacity is the spec that counts, and not how soft the towel feels in the shop. People often ask which GSM microfibre cloth is best for a car, but GSM only tells you how dense the fabric is. What you actually want to know is how much water the towel holds before it stops taking any more.
The iZi-Dry Towel M is 60 by 40 cm and holds up to 800 ml of water. That is deliberately the same size as the Wonder Cloth, big enough to take a panel in one pull. The fibres are twisted and do not shed lint, which on glass and on dark paintwork is exactly what makes the difference.
What you do this with
Two cloths, and the whole car is covered. Inside and out.
- iZi-Dry Towel M · 60 x 40 cm, up to 800 ml, the towel for the drying
- iZi-Clean Wonder Cloth, pack of 12 · 60 x 40 cm, for windows, dashboard and interior
- Dark Pack, pack of 4 · anthracite, handy for the dirtier jobs
Frequently asked questions
How do you wash a car without streaks?
Work in the shade, rinse off well and take the water straight off with a towel that holds enough. Streaks do not appear while you are washing but while the car is drying, on the spot where a drop stayed put and dried in.
Should you towel dry your car after washing?
Yes. Leave it to drip dry and every drop dries in on its own spot, and the limescale that was in it stays behind as a mark. It is fine to dry your car with a towel, as long as it is a microfibre drying towel and not the bath towel from the airing cupboard. That last step decides whether the car looks sharp or ends up covered in rings.
What is the best thing to dry a car with?
A large microfibre towel that takes up plenty of water. Not a chamois and not a bath towel: a bath towel pushes the water ahead of it instead of lifting it up. The iZi-Dry Towel M is 60 by 40 cm and holds up to 800 ml, enough to get round the car in one go.
Do microfibre cloths scratch the paintwork?
A clean cloth does not, because it is softer than your clearcoat. What does scratch is the grit or the brake dust that has worked its way in between the fibres. So never take a cloth to a dry, dusty car, keep your wheel cloth apart from the rest, and put any cloth that lands on the ground straight in the wash.
How do you get water spots off a car?
Wash the car again with plenty of water and dry it immediately, without letting it drip. Use no vinegar and no other acid on paintwork, rubber or chrome: it dissolves the lime, but it attacks what is around it too. If a mark is really baked in, that is a job for a paint specialist and not for a home remedy.
Can you wash a black car without streaks?
Yes, but you have less room for error. On dark paintwork you see every dried drop, so the order counts for most of all: shade, a thorough rinse, and drying straight away with a towel that is not full halfway round. Work panel by panel instead of hosing down the whole car first.
How do you wash car microfibre cloths?
At 40 degrees, with washing powder or a splash of vinegar instead of fabric softener. No liquid detergent, no pods or capsules, and never in the tumble dryer. Fabric softener leaves a coating around the fibre so the cloth stops taking up water, and that is exactly why a good cloth suddenly starts leaving streaks.
Join the iZi-Clean community
Streak free drying with nothing but water, like more than 300,000 households already do. Inside, outside, and on the car just as well.
See the drying towels14 days to change your mind. Questions? You can simply reach us.
iZi-Clean is a registered trade mark. More on the difference between working dry and working just damp in What is the best drying cloth for the bathroom?