While in a rush to get out, I put the fluid in the wrong place. The car has not overheated but I have smelled the fluid evaporating. There is no difference in engine temperature or running condition. Its a 2002 civic LX with the non vtec motor. Can I leave it in to evaporate or should I change the fluid?
unless your car has a coolant leak it will not evaporate as cooling systems are considered sealed, unless they have leaks. you need to flush your coolant, probably a few times. the cheapest way to do this is to drain and fill with DISTILLED water 2 or 3 times. and afterward, refill with the proper coolant. washer fluid is not compatible with coolant and will cause rusting of the radiator and engine block.
I use Bar's Leak for those that can't afford to get the job done right away and need time to fund enough money for the job. It works 90% of the time and helps keep the vehicle going until they can afford to do the job right. It is in noway a permanent fix unless the leak is very small. Once the problem is fixed I double flush the system and add the correct amount of antifreeze. Since the leak is coming from the heater core you could just bypass it until you get it replaced. No need for stop leaks there. Easy fix.
Head gasket will smell at tailpipe like anti freeze when you start the engine or build pressure in cooling system until it blows out the overflow. Heater core is probably leaking need to replace it or disconnect the two heater hoses and couple them together to bypass heater core. See if that stps your antifreeze loss. Then you'll know. But you won't have heat.
You should remove the wiper fluid from the resevoir. Unbolt the resevoir and clean it out if you have to. Then only put 50/50 premix antifreeze into it. Do you wish to risk harming your vehicle for this ?
Change the fluid. What's that gonna run you? About $6? I'd rather spend the $6 change the fluid and know that everything's okay than leave it in there do some irrepairable damage and have to buy a new car. Windshield wiper fluid is heavily alcohol based. It evaporates quickly so that it doesn't leave streaks. Anti-freeze is polyethylene glycol. It's designed to keep your engine cool. It stays consistently the same viscosity no matter what the temperature is. Either way, it's a bad idea to be trying to cool your engine with alcohol. CHANGE IT.