kinda a loaded question that's prone to personal oppinion.
I can tell you what "I" do. Others will disagree with me.
Some engines tolerate water better than others. If I were to do my little Ford Escort while it was running the belt would imediately fly off. With the truck it wouldn't be so much of a problem.
Here's what "I" do.
1. Cover Computer and CAI with plastic bags.
2. If heavy with mud I will soak with water then rinse with full flow but low pressure water.
3. Spray everything down with Meg's APC+ dilluted 4:1
4. Before it has a chance to dry spray with pressure washer with a low pressure nozzle.
5. Remove the plastic bags.
6. Then blow as much water off as possible with a gas leaf blower (paying special attention to getting water out from the areas around the plugs and coils)
7. Spray everything down with Meg's Hyperdressing 10:1
8. Dab excess H.D. as best I can with MF towel.
9. Start motor till mostly dry.
One example of a farm truck I did last summer.
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