It has been asked a few times about washing and engine compartment and the concern for getting electrical parts wet causing issues.
So here is a few basic common-sense things to think about when washing your engine.

1. Use on a garden hose with your house water pressure regulated at no more than 60psi. The normal for most residentials is 40psi.
2. If you want to use soap, use the same soap as you would wash you exterior. DO NOT let the soap dry or set more than 5-10 minutes.
For oil or grease use simple green sparingly and rinse off after no more than 3-5 minutes. use your soap to spray again and then rinse off.
3. never blast the water in one locatio0n for more than a few seconds, even if there is a buildup of oil grease. You will need to do a couple of cleaning and possibly using a clean paint brush to brush the area a little with simple green and then rinse a few times to remove the grease and oil.
4. DO NOT wash and rinse the engine compartment more than 10 -12 minutes. You may not get it completely cleaned if this is your first time and you may need to clean it again in another couple weeks or month. Weather dependent. It is always better to wash the engine when you can leave the hood open for at least an hour after your wash it.
5. On your final rise you will want to take a clean rag or towel and start to soak up the few puddles of water in and around the intake manifold. Don't worry about drying every spot not only is it impossible but not needed. If you have a compressor, you can, use a control air nozzle that will get into more areas and blow the water off. But again, this is not necessary. The engine compartment will completely dry in 24-36 hours if you normally drive each day.

Most all Mazda (generally other platforms as well) use seal lock electrical connection. They are waterproof.

Some common sense should be done when considering washing your engine. If you have an exposed air filter wrap it in food or cling wrap. If you have a battery with dirt terminals clen then before washing the engine. Don't blast high pressure water dirty at your condenser or you couple bend the fins.
Aside from those few that is really about it

 

 

 

Thank you very much for this thread! I've been wondering for a while now and was concerned about the connectors. Everything you posted makes perfect sense (of course, it's you) so I'll keep this in mind when I clean the compartment as soon as time/weather let me.

Great thread!
Endy.