Module 3: Engine Bay & Wheels

A car may appear to be in excellent condition on the outside, with a clean and shiny paint job, but when you look under the hood, the engine bay may be filthy, detracting from the overall experience. That is how car detailing differs from a regular car wash.

Car detailing ensures that a vehicle looks good on the outside as well as the inside. The engine bay is a critical part of this. In this unit, we’ll go over how to inspect and clean the engine bay and wheels, as well as the best products to use, and how to breathe new life into the engine bay, making it look brand new.

Engine Bay and Wheels

The engine bay can accumulate lots of grime over time. Unfortunately, many car owners don’t pay enough attention to the cleanliness of the engine bay. Because of this, there can be years of built-up grime and dirt in the engine bay that can be hard to get rid of.

Before cleaning the engine bay, it is important to cover up any engine parts where contact with water should be avoided, such as the air intakes, alternator, coil packs, Electronic Control Unit, On Board Diagnostics, and other electronics. Cover these parts with a plastic bag, attached with tape or an elastic bag. This will help prevent damaging the parts.

Degreasing the engine compartment is the first step to cleaning the bay. You should apply a degreasing product to cover every inch of the engine bay. After letting the degreaser do its magic, you can wipe it away, along with all the dirt and grime.

If there are still spots where dirt remains, you can use a small brush to gently work the degreaser in.

Clean the outer edge of the rim using a rag, sponge, or other type of cleaning tool. Scrub until all of the grease is gone. Next, clean the interior of the rim while being mindful of small crevices. Toothbrushes can be a good option to reach tiny areas.

Many car owners take pride in their wheels. Indeed, it’s one of the first things that catches an eye when looking at a car.

In auto detailing, it’s important to pay enough attention to the wheels and make them clean and shiny. There are dedicated wheel cleaning solutions that will bring back the shiny look as if it were fresh out of the showroom.

Using dedicated wheel cleaners can guarantee a great result, but if the dirt is moderate, the goal can also be achieved with simple car soap or shampoo. You can use small brushes or even toothbrushes to get to the hard-to-reach spots.

Mistakes to Avoid

When working on the engine bay several things that could go wrong.

There are many parts in the engine bay that may get damaged during degreasing and washing, such as the air intakes, alternator, coil packs, Electronic Control Unit, On Board Diagnostics. Before getting started on cleaning the engine bay, make sure that these parts are properly covered to avoid damaging them.

As for the wheels, if using the specialized cleaning solution, make sure to read how it’s supposed to be applied.

When dealing with chrome or alloy wheels, you can run the risk of ruining them if you keep the product on them for too long, so make sure you’re using the right product for the metal and use it correctly.

Wheel Materials

Most often, car wheels are made of steel, the cheapest option on the market. They are sturdy and can withstand years of use, but over time they can deteriorate and even form rust.

Another commonly used material for wheels is an alloy of aluminum. They used to be reserved for luxury models, but slowly they’re becoming more widespread. They are much lighter than steel and are way less likely to erode.

Chrome finish is another option that many car users opt for. The chrome coating protects the wheels from the environment and gives them exceptional shine.

While all these materials can be cleaned and washed, you must be careful not to misuse wheel-cleaning products, because if used in excess, they can damage the outer coat.


Detailing the engine bay and wheels consists of two parts. The first step is to clean them, and the second is to dress them to protect them from further damage.

When cleaning the engine, a degreaser is essential. You can’t take off all the oil and dirt from the engine bay with simple cleaning solutions like soap and water. After you have thoroughly degreased and cleaned the engine bay, you can use engine dressing to give it a fresh look.

The same goes for the wheels. After cleaning them, you can use protectants, like wheel seals or wax, to ensure their longevity.

Working More Efficiently

In auto detailing, work efficiency is crucial. You must be able to deliver the best results in a short amount of time, so the customer is satisfied.

Cleaning the engine bay and wheels can be a challenge, especially if they have years of built-up dirt on them. But by following the steps outlined in this unit, you can get it done in no time.

Knowing what products and supplies to use, as well as the order in which to perform the steps, is essential for efficient car detailing.

Dressing the Engine Bay

After thoroughly degreasing and cleaning the engine bay, you can move on to dressing the parts. Many customers are after a shiny look that breathes new life into their vehicles.

The key to a successful dressing of the engine bay is cleanliness. If there is still residue oil or grime stuck to the motor and other parts, no amount of dressing will be enough to achieve a uniform, shiny look.

There are specialized engine dressings available, but because the parts are mostly made of plastic, you can also use all-purpose car dressing.

Proper Use of Tools

While cleaning the engine bay and wheels, you must use the correct tools and products to avoid unsightly scratches or discoloration.

It’s tempting to scrub away at the engine bay in an attempt to get rid of the built-up grime but letting the degreasing product do its job is always better.

To conclude, you should be careful not to overuse some products, and be patient and trust the process to achieve the maximum result.