Engine bay wash
Thread Starter
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For the last 40 years, I've dumped the remaining wash bucket over the top of a cold engine then rinsed with the hose. No ill effects. If an engine is really dirty, I'll spray some degreaser (I like Zep 505 from HD), let it sit, agitate with a brush, then scrub with a bucket of Dawn wash. Dump the remaining over, etc.
Don't aim the hose at electrical components and use a wide spray pattern for gentle rinsing. Any scrubbing should be by hand, don't use water pressure to clean.
Don't aim the hose at electrical components and use a wide spray pattern for gentle rinsing. Any scrubbing should be by hand, don't use water pressure to clean.
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From: PNW
Salt-Away
If there is a lot of dried salt, you could try Salt-Away product. We use it on the boat after being in salt water and it works pretty well removing salt spots.
Amazon:
Amazon:
Drifting
Joined: Oct 2023
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You can wash the engine bay by following these guidelines:
1/ The engine must be cold.
2/ The water must be applied at very low pressure. Warm water is more efficient (if possible).
3/ Do not use harsh chemicals, as this will damage aluminum components.
4/ Try to avoid electrical and electronic components.
5/ Be very careful with water spraying from the side of passenger compartment. This area contains the most electronics and has soundproofing mats that absorb water.
6/ After washing, remove the air filter housing and thoroughly blow out all corners of the engine with compressed air.
7/ If possible, leave the car with the hood open for a few hours to allow any moisture to evaporate.
1/ The engine must be cold.
2/ The water must be applied at very low pressure. Warm water is more efficient (if possible).
3/ Do not use harsh chemicals, as this will damage aluminum components.
4/ Try to avoid electrical and electronic components.
5/ Be very careful with water spraying from the side of passenger compartment. This area contains the most electronics and has soundproofing mats that absorb water.
6/ After washing, remove the air filter housing and thoroughly blow out all corners of the engine with compressed air.
7/ If possible, leave the car with the hood open for a few hours to allow any moisture to evaporate.
Thread Starter
Rennlist Member
Joined: Apr 2019
Posts: 5,854
Likes: 3,104
You can wash the engine bay by following these guidelines:
1/ The engine must be cold.
2/ The water must be applied at very low pressure. Warm water is more efficient (if possible).
3/ Do not use harsh chemicals, as this will damage aluminum components.
4/ Try to avoid electrical and electronic components.
5/ Be very careful with water spraying from the side of passenger compartment. This area contains the most electronics and has soundproofing mats that absorb water.
6/ After washing, remove the air filter housing and thoroughly blow out all corners of the engine with compressed air.
7/ If possible, leave the car with the hood open for a few hours to allow any moisture to evaporate.
1/ The engine must be cold.
2/ The water must be applied at very low pressure. Warm water is more efficient (if possible).
3/ Do not use harsh chemicals, as this will damage aluminum components.
4/ Try to avoid electrical and electronic components.
5/ Be very careful with water spraying from the side of passenger compartment. This area contains the most electronics and has soundproofing mats that absorb water.
6/ After washing, remove the air filter housing and thoroughly blow out all corners of the engine with compressed air.
7/ If possible, leave the car with the hood open for a few hours to allow any moisture to evaporate.
Drifting
Joined: Oct 2023
Posts: 2,324
Likes: 1,647
No, it's important to thoroughly blow out the water with compressed air also to avoid leaving white water spots. Driving the car immediately after washing is the worst solution because it increases the humidity in the engine compartment (water vapor - sauna effect), which causes moisture to get into all the nooks and crannies, including the electrical contacts.
Thread Starter
Rennlist Member
Joined: Apr 2019
Posts: 5,854
Likes: 3,104
No, it's important to thoroughly blow out the water with compressed air also to avoid leaving white water spots. Driving the car immediately after washing is the worst solution because it increases the humidity in the engine compartment (water vapor - sauna effect), which causes moisture to get into all the nooks and crannies, including the electrical contacts.
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Joined: Nov 2019
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From: Idaho
No, it's important to thoroughly blow out the water with compressed air also to avoid leaving white water spots. Driving the car immediately after washing is the worst solution because it increases the humidity in the engine compartment (water vapor - sauna effect), which causes moisture to get into all the nooks and crannies, including the electrical contacts.
The notion that issues are created if the vehicle is driven after the engine is washed is ridiculous.
Drifting
Joined: Oct 2023
Posts: 2,324
Likes: 1,647
Anyway, wash your engine as you like.
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From: Massachusetts
I would just use some salt neutralizer in a pump sprayer and then gently rinse with fresh water in a small pump sprayer (like a garden sprayer). Stay away from the ECU
Here's a pic of my pump sprayer with salt neutralizer off in the corner of the wash bay
photo553.jpg
Here's a pic of my pump sprayer with salt neutralizer off in the corner of the wash bay
photo553.jpg
Last edited by 95_993; Jan 7, 2026 at 08:51 PM.
Rennlist Member
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From: Idaho
That's your theory. Mine is different, and I don't think it's rediculous but it's supported by years of experience. When washing an engine, you pour water into areas that don't get wet during operation. This includes the turbocharger, exhaust manifold, alternator, and many other electronic components.
Anyway, wash your engine as you like.
Anyway, wash your engine as you like.
Driving the vehicle after washing the engine is beneficial, not detrimental.
Drifting
Joined: Oct 2023
Posts: 2,324
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Rennlist Member
Joined: Nov 2019
Posts: 3,673
Likes: 2,877
From: Idaho