I posted this previously in another thread, but this information belongs here as well.
Aftermarket engine air filter cleaning (AEM Dryflow)
Since this is not an oiled filter, all you have to do to clean it is spray down the filter with water from the inside out, using a garden hose (do not use a pressure washer). This will push the dirt and other contaminants outwards. In this case, I decided to go a step further and gently wet the filter, then dump it in warm soapy water. I used Dawn dish detergent. I moved the filter around a little bit to agitate it, hoping the soap would help to lift more dirt off the filter element. After that, I used my garden hose to spray the filter clean from the inside out as usual, making sure that the water rinsed clean with no soap bubbles. Following that, I swung the filter around in a circular motion to get as much water out of it as possible, then left it to sit in front of a fan to dry it out.
Engine bay cleaning
When I clean my engine bay, I only do it at the end of the day, or when I know the car can just sit for a while, just in case I happen to get water somewhere I shouldn't. Letting the car sit just allows the water to drain off and evaporate a bit, though I'm not really sure its necessary with how well sealed the majority of the engine electronics are. It's also a good idea to clean the engine bay when it is either warm or cool to the touch. If the engine is hot, you could accidentally burn yourself.
Because I have an aftermarket air intake, I would either remove the filter and plug the hole, or wrap the filter in a plastic bag and secure it to the pipe. In this case, because the filter was already off of the car, I just plugged the hose, taking care not to damage the MAF sensor inside the pipe.
Then, to protect the electronics, you can put a plastic cover over the battery and the alternator. If you want to clean under the engine cover, you may also want to cover some of these areas too, though I'm not sure if its necessary. I did all these things the first time, but this time, all I did was disconnect the negative terminal on the battery and keep the engine cover on during cleaning.
On to the actual cleaning. First, I sprayed down the engine bay and the underside of the hood with water using my garden hose. It may not be ideal to use a pressure washer in this case, mostly because the high pressure can force water into areas that water shouldn't get through, like through the gaskets in the electrical connectors. All you really want to do is get the areas to be cleaned wet.
With the bay now wet, you can apply your degreaser. I used SuperClean. If your engine bay is particularly dirty, like mine, you can apply liberally, or even do more than one application after letting the first one sit for a couple of minutes. After applying the degreaser, you'll want to agitate the surfaces to lift the dirt off. Most brushes or towels will work just fine for this, but I like to use a wheel brush with a design like the
EZ Detail wheel brush. This style lets you get into the tighter areas, like around the battery for example. I like to clean the hood first, then hose it off, and do the engine bay afterwards. Once you're done with the brush/towel, you can rinse off the remaining degreaser. Again, try not to get too close with the hose or use a pressure washer. All you're doing here is rinsing off the stuff you already loosened with the brush.
Now, you can give the engine a quick wipedown to dry it off. You can also use this opportunity to wipe clean any areas you may have missed. At this point, you can call it done and remove the plastic bags from the covered areas, then gently and carefully hand clean those covered areas. Alternatively, you can use a leafblower or even a hairdryer to blow the water out of the nook and crannies of the engine bay, again just be careful not to get too close or you may force water into areas that it should be able to get into. Then, reinstall the air filter if you removed it. Make absolutely sure that you remove whatever you used to plug the air intake hose if you plugged it during cleaning. Finally, reconnect the battery if you disconnected it instead of covering it. You can call it done at this point, but if you'd like to dress the engine a bit, read on.
There are a lot of engine dressing/detail products out there, but I just use Aerospace 303 because I already have it. I like to spray the entire engine bay down, excluding the air filter, to coat the components. Then I like to leave the car to sit for a few hours to let the product dry on its own. Then I'll wipe up any remaining product. This leaves a nice, shiny, almost glossy look to most parts of the engine bay. With that said, if you don't want to waste time or product (like me), or if you want more of a satin, low-gloss finish, you can spray your product onto a microfiber towel and wipe it onto the areas you want to dress.
And you're done! Before you start the car up again, just try to make sure the air filter is dry (if you got it wet or cleaned it). The car will likely be safe to drive immediately after cleaning even if the alternator or other electrical components got wet, but I prefer to just let the car sit for a few hours.
Here's a quick video of me cleaning the engine bay:
*** AUDIO WARNING *** At around 5:00, when I start using the blower to dry the engine bay, there is a high pitched noise that starts when the video is sped u...
youtu.be
Hope that helps!