We all do things a little difference I refuse to put water on the engine while it is running for fear of shorting out the wires in the sensors, and belive me, on a older car the "gaskets" have somewhat worn out. Therfore what I do is:
1. Remove headliner, pressure wash it.
2. Let engine cool to the point that water can be sprayed without it steaming.
3. Cover all electrical components with duct tape, I cover the alternator, and coil packs the best I can, also ICM connection and other conenctions I can see, wrap a layer of tape around them to prevent water, alternator is the big one MAKE SURE you cover that good if you are going to be using high pressure water. Remove Air intake box, cover TB with duct tape
4. Spray engine area, everything with a mild cheap degreaser, I use the 97 cent walmart stuff, 4 cans. get everything foamed up so it looks white, i mean white as in bright white curse white.
5. Apply a coat of windex to the hood, spray in the holes, spray windex on the exposed paint areas in the engine bay, apply engine degreaser to the underside of the hood in the holes and such and make it all foamy, at this point you also need to apply more engine degreaser to the engine as some of it will turn greasy brown color.
6. let sit for 5 minutes. or remember we are in a carwash right now, so spray off the rest of the car
7. Spray engine and underside of hood, and all surfaces with presoak, then spray it hard for about 8 minutes with the high pressure soap mixture.
8. Then spray it with the rinse for at least 7 or 8 minutes to get all the engine degreaser out of everywhere, finally finish it off with the non-spot rinse. Do this for about 5 minutes, hit everywhere.
9 Get out the compressed air, remove connections to the TB, spray out, spray out connectors. Remove the plug wires from coils, spray those out with compressed air. Sray out any water that sneaked into the alternator out with compressed air as well.
10. Wipe down eveyrthing, underside of hood everything you can, roll up the paper towel and make sure you extract every bit of water from the holes or indentations in the lower intake mainfold.
Then you wait, smoke a ciggerate or something. finish washing the wrest of the car wipe it down wax it whatever.
Finally start engine, if you did it properly there should be no smoke
from the engine degreaser.
Sound time consuming, yes it is, but it is worth doing once a year or so.
Final product is this: