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best cleaning products for engine bay

The Best Engine Degreaser 2019

Overtime, the engine bay will become dirty with debris gradually building up. However, engine detailing can be made simple yet effective with a quality engine degreaser that is safe to use under the hood and will not damage any electrics.

The best engine degreaser is the Simple Green 19128, which is a non-hazardous, non-flammable, non-corrosive and fragrance free solution yet is still very effective.

Using a regular car wash soap and wax can remove some dirt from within the engine bay but may leave the plastics (such as the engine covers) with water/soap spots. Using an engine degreaser will remove the tougher dirt and leave no defects.

Best Engine Bay Cleaners

Engine DegreaserTypeSize
Simple Green 19128 CrystalSpray1 Gallon
Meguiar's Super DegreaserSpray1 Gallon
WD-40 SpecialistAerosol18 oz
Gunk Original Engine BriteAerosol15 oz
Chemical Guys All Clean+Spray16 oz

Taking your car detailing process to the next step with an engine degreaser can make all the difference. Many people will avoid this type of detailing as it can be fairly easy to damage an expensive component of the engine with the incorrect process. However, with a proper engine bay cleaner and process, you are able to return the engine bay to a factory finish.

Regularly detailing your engine bay will not only make it look nice but also reduce debris building up in any air intakes. Below is a list of the best engine degreasers that make cleaning under the hood effortless and safe with no risk of damaging parts.

Simple Green 19128 Crystal Degreaser

Simple Green is one of the safest engine degreaser cleaning products you can buy. The Crystal formula is a non toxic, non-hazardous, non flammable and non-corrosive. In terms of engine bay detailing, they are all features that you want see as imposing danger under the hood is not advised.

In terms of the notable features of the Simple Green Crystal, they include:

  • Biodegradable
  • Fragrance free solution
  • Highly concentrated
  • No added coloring
  • Can be used on other parts

As the Simple Green formula is highly concentrated, we recommend that you dilute it within a spray bottle. This makes the engine degreaser last far longer and add extra bang for your buck. Overall, it is the best engine degreaser that is safe to use on all automotive engines and other parts.

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Meguiar’s D10801 Super Degreaser

Meguiar’s is a big brand that everyone in the detailing industry will know about. However, calling their engine bay cleaning product a “super degreaser” is a bold claim and it can be used in a range of different situations.

In terms of the notable specs of the Meguiar’s Super Degreaser, they include:

  • Powerful but can be diluted
  • Herbal fragrance solution
  • Residue free performance
  • Breaks down in the toughest of dirt

This degreaser can be used for automotive exterior use only but cleaning an engine bay is where it really becomes “super”. The strong formula breaks down tough dirt that has been under the hood for years with ease. Overall, it is the best engine degreaser for the money when bought as the 1 gallon size.

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WD-40 Foaming Engine Degreaser

WD40 isn’t the first thing you would think of for engine bay detailing but they have a dedicated degreaser for the job. The normal WD40 is renowned for removing squeaking noises, lubricating components and much more but is this product is specific for degreasing.

Below are some of the features of the WD-40 engine degreaser:

  • Removes all types of dirt
  • Low residue foaming formula
  • Nozzle sprays up to 5 feet
  • Smart straw is included

As with any WD40 spray, there is a dedicated nozzle that you can use to target hard to reach spots within the engine. Even if its far away, the long distance spray will be able to reach it. It is an engine bay cleaner that provide superior accuracy, which is great for those cramped engine bays.

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Gunk FEB1 Foam Engine Bay Degreaser

Gunk have a range of products that deal with degreasing engine bays to garage floors. The DEB1 Foamy Engine Brite Degreaser is very popular worldwide with great results. As mentioned in the product name, it is foam based that clings to dirt, dust and road grime to safely remove it.

The Gunk formula is safe to use on plastics, rubber and paint and is proven to be one of the toughest cleaners on the market for over 55 years. It is that powerful, there is no need to rub the solution into the dirt, just wait 15 minutes and wipe it down.

As it is an aerosol, it is also straight forward to use with no dilution required beforehand or difficult to use spray bottle. Overall, it is a cheap and powerful engine bay degreaser that can removes almost all dirt hassle free.

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Chemical Guys All Purpose Super Cleaner

At ProCarReviews, we are huge fans of the Chemical Guys detailing products as they are specialized for each purpose and offer great value for money. Their engine degreaser gives a great citrus smell and removes tough dirt with ease.

The All Clean+ is a natural cleaning formula with a hint of citrus that effectively removes tough dirt from any surface. Unlike the other products, it can also be used on the interior of your vehicle to also remove stains and odors.

Its most effective on engine bays and undercarriages for removing grime and tar upon contact. This Chemical Guys products takes the meaning of “All Purpose” to the next level and is definitely the best overall degreaser for all aspects of detailing.

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Engine Degreaser Buying Guide

Although the engine is tucked under the hood, it still becomes quite dirty overtime. The majority of car owners will not go near their engine at all but for those that are serious about detailing, it can be a rewarding job to accomplish. All the thick and tough dirt can be easily removed with a powerful engine degreaser that is effective at removing dirt and of course, being safe.

Cleaning your engine bay isn’t the most enjoyable job and therefore you will want it over and done with quickly. Using a simple soap or home remedy will usually require a fair amount of scrubbing and this is why you should stick to a degreaser. Below is a guide on how to clean your engine bay effectively.

Engine Degreaser

How To Clean Engine Bay

As mentioned, cleaning the engine bay require a delicate touch with many horror stories being told online. The potential to damage expensive electrical components can be quite daunting. You will often find people using their powerful pressure washers and if used incorrectly, it can cause a damage such as piercing the wiring loom or damaging sensors.

However, the benefits of cleaning your engine bay include an increased sale price, easier to work on and obviously its more aesthetically pleasing.

Below is the safest method of cleaning an engine bay without water:

  1. Prepare The Engine. With the engine cold, you will want to remove loose debris and cover electrical and delicate parts. These parts include air intakes, sensors, ignition wires and coils.
  2. Removed Baked Dirt. Due to the heat that an engine produces, the dirt can become “baked” on the engine. To remove this type of dirt, simply use a wired brush and remove the tough dirt.
  3. Apply Engine Degreaser. Using a recommended engine bay degreaser above, spray down the work area and let the product get to work by leaving it for at least 30 seconds. You will then need to use the wired brush again and work in the degreaser to tough dirt.
  4. Dry The Cleaner. After the scrubbing of the degreaser, use a microfiber towel to remove the solution on your engine bay. The engine bay should be clean and ready for additional detailing products if required. Ensure that there are no pools of degreaser under hidden compartments or wires.
  5. Increase Shine and Protect. It is the best time to add additional shine and protection to the engine bay once degreased. Using the recommended detailing products mentioned in this article, spray onto the microfiber towel (A new one) and rub onto the engine bay. Avoid spraying directly because this can leave abrasive markings.

If you were to use water based methods, you would use a pressure washer on the widest setting to spray away the degreaser. The most important thing to remember is not to spray over the covered areas because the plastic you used will simply split leaving it exposed.

Personally, there is no need to use water as you will get the same results with or without water. You are just adding additional risk to your engine bay. For a complete guide to engine bay cleaning, check out this detailed guide.

Engine Bay Cleaner

Types of Engine Degreaser

Not all engine degreasers are the same and some are petroleum based and others are water based. The petroleum engine degreaser is the strongest and the cheapest as it doesn’t use expensive ingredients in the formula. The main drawback is the fact that its more abrasive, which means it should only be used on the specified surfaces. These will be stated on the product but it will more than likely say most plastics and other components.

Water based engine degreaser alternatives are mire safer to use and can usually be used on a range of surfaces. Therefore you do not need to worry about a small amount of overspray. The formula is far more advanced in order to make it a safe degreaser to use on cars but this does not mean its not as effective.

Engine Detailing

Once you have successfully used an engine degreaser on your engine, you can take things a few steps further. Many people will opt for an engine dressing formula to provide a sleek finish. Some car owners even use a tire shine as a dressing on their plastics under the hood. However, be sure to check on the back of the product on whether it can be used as the engine will reach high temperatures. This will have the effect of heating the product up and turning it a different color.

Depending upon the age of the vehicle, you may even have faded plastics too. This can ruin the look of your engine bay but there are many different types of plastic restorer products that will return the fade to a more attractive black.


The engine bay can sometimes never be cleaned but for those that are serious about detailing, its a job worth doing. From simply using an engine degreaser to performing a complete engine detail to return it to factory condition.

There are various different methods of cleaning under the hood but using the best engine degreaser you can find is the safest option. Its simply not worth using a highly abrasive or powerful pressure washer on the engine as the damage when things go wrong can be expensive.

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