CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Dirty Windshield from coolant

There was a coolant leak in my grand am that I have fixed, basically the coolant under pressure would drip onto the exhaust manifold and steam away… now there is a film that I am unable to clean on the windshield with regular cleaners like windex etc. I remember there was a car talk episode where they talked about how to clean the coolant of the windshield… ideas?

You can try white vinegar mixed in water. But the coolant should readily mix with water alone and be diluted to a point where it’s totally rinsed away. Have you tried washing the windshield off with a water hose or at a car wash? Unless there’s something else on the windshield?

Tester

Definitely tried water hose/ car wash etc, the residue is also on the inside, when I bought the car the coolant leak was there along with the stained windshield, so it could be something else but not sure.

If the film is also on the inside of the windshield, and you just got the vehicle, it might be vinyl off-gassing residue. Purchase a can of Brasso metal polish and clean the inside of the windshield with that.

Tester

You also may try BonAmi cleanser in the Yellow can not the Gold can. The gold can is more aggressive and may scratch the windscreen, as many other products can. I don’t know about Brasso on glass, but I do know Tester and he is seldom wrong.

I’d try a citrus based cleaner, and then wash it off with regular car cleaning stuff.

There are many things that are safe to try on glass (but be careful not to get them on your paint). I’d suggest trying isopropyl alcohol next. (I use this all the time as the final step in my window cleaning routine to remove any streaks.)

For future reference, if coolant is getting inside the car, you want to fix the problem quickly. Coolant mist is bad stuff to breathe in.

You may also have a leaking heater core. The heater core is inside the dashboard, and that’s the usual place for a coolant leak that deposits on the windshield.

Just as a side note; if used on the dash, certain vinyl cleaners/conditioners, i.e. “ArmorAll” type products will leave a film on the inside of the w/s as they evaporate. If you use these avoid the dash area.