Why Can't I Get My Windscreen Clean?

[Ala Larj]

I have tried many products and methods to clean the inside of my windscreen to no avail. I always end up with a sort of patchy haze which looks like it's steamy up slightly but the AC doesn't seem to get rid of it. It looks worse in bright sunlight (ok, not a major problem!). It's driving me nuts. Have never had this problem with other car brands. Am wondering if Lexus put some sort of stuff on it to prevent misting? Have noticed the screen is not an original Lexus but a replacement Pilkington one. I believe it's correct as it has the elements in the bottom for the wipers. Does anyone else have this problem?

[Shepherd]

I always have the AC at auto ON and get no haze. If I turn the AC off I start to get haze. Keeping the AC on does not seem to make any differece on the mpg.

Do you keep your AC at auto on?

[Carl911]

I agree, keeping the AC on doesn't seem to effect the economy plus I find with it on the tickover its so smooth I can't feel the engine is even running.

[Ala Larj]

Thanks. I do tend to switch it off but assume that any misting should disappear when I use the screen demister.

[dazed]

I have tried many products and methods to clean the inside of my windscreen to no avail. I always end up with a sort of patchy haze which looks like it's steamy up slightly but the AC doesn't seem to get rid of it. It looks worse in bright sunlight (ok, not a major problem!). It's driving me nuts. Have never had this problem with other car brands. Am wondering if Lexus put some sort of stuff on it to prevent misting? Have noticed the screen is not an original Lexus but a replacement Pilkington one. I believe it's correct as it has the elements in the bottom for the wipers. Does anyone else have this problem?

I can sympathise with you on this one as I've always found it difficult to get a really clean windscreen on the inside. Sometimes, attempting to 'clean' it can actually make it worse. The awkward access doesn't help either.

Basically, you just need a half decent glass cleaner (I'm currently using Autoglym Car Glass Polish which seems more effective than anything else I've tried in the last few years), a clean cloth and plenty of elbow grease - and I mean plenty!

A couple of other tips:

1. Do the job on a warm, dry day.

2. Park the car facing into the sun - that will show up all the smudges and streaks really clearly as you work on the glass.

[normski2]

@dazed, totally agree with you.

Just don't do it on a really hot day, slightly overcast works best I find. Yes the access is a bit of a toad too.

[The Editor]

You're fighting a bit of a losing battle over here because the tree hugging nanny state brigade in the UK have outlawed glass cleaners with amonia which work the best. The off the shelf rubbish which is sold with vinegar and lemon juice etc are all pretty rubbish (compared with ones with amonia).

Your best option would be to clean the inside as best you can with an off the shelf product to get the worst off. Then get some methelated spirits and clean the inside with that. This will get rid of any film that remains and will evapourate quickly.

You can also use meths on the outside of the windscreen etc for excellent results.

[Ala Larj]

Thanks. When's that warm day coming Dazed? Might give auto glym a go. I use their stuff for the paintwork and am impressed with the results.

[Postman]

Thanks. When's that warm day coming Dazed? Might give auto glym a go. I use their stuff for the paintwork and am impressed with the results.

You don't particularly need a warm day. It's a dry day you need when the temperature and dew point spread is more than a few degrees. I would second the Auto Glym Fast Glass. I've been using it for years. It's a good idea to have the aircon switched on too as it should dry out the air coming into the cabin which helps keep the screen clear and indeed the rest of the windows.