Best Engine Bay Cleaners & Degreasers (2026)

For most engine bays the safest pick is a near-neutral ready-to-use cleaner like Griot's Garage Engine Cleaner (pH 8, RTU); for greasy, neglected bays a dilutable alkaline degreaser such as P&S Hot Shot (up to 1:15) or Dodo Juice Release The Grease (1:1) cuts baked-on oil far faster.

Last updated: 2026-06-17 · 7 products compared · Data: manufacturer documentation & SDS, via the Find Your Detail catalogue.

ProductBrandpHDilutionBest for
Griot's Garage Engine CleanerGriot's Garage8RTUplastic-safe, ready-to-use
McKee's 37 Engine DegreaserMcKee's 37RTUspray-on RTU degreaser
Sonax Engine CleanerSonaxRTURTU spray, easy rinse
Auto Glym Engine & Machine CleanerAuto GlymalkaliRTUalkaline, water-rinseable
Car Gods Bay Immaculate Engine CleanerCar GodsRTU ~ 1:10dilutable to soil level
Dodo Juice Release The GreaseDodo Juicealkali1:1alkaline degreaser, dilute 1:1
P&S Hot Shot High Power Degreaser ConcentrateP&SalkaliRTU ~ 1:15heavy-duty concentrate
  1. Griot's Garage Engine Cleaner — pH 8, ready-to-use — near-neutral, water-based cleaner that is safe on plastics, rubber and sensors; the low-risk maintenance pick.
  2. McKee's 37 Engine Degreaser — ready-to-use — spray-on, agitate and rinse; convenient no-mix option for light to moderate grease.
  3. Sonax Engine Cleaner — ready-to-use — straightforward spray-on engine cleaner that rinses freely; widely available OE-grade pick.
  4. Auto Glym Engine & Machine Cleaner — alkaline — cuts oily film on engines and machinery; keep off very hot parts and rinse thoroughly.
  5. Car Gods Bay Immaculate Engine Cleaner — RTU up to 1:10 — flexible dilution lets you dial strength from a light refresh to a neglected bay.
  6. Dodo Juice Release The Grease — pH alkaline, 1:1 — strong alkaline degreaser for baked-on oil; agitate with a brush and rinse promptly.
  7. P&S Hot Shot High Power Degreaser Concentrate — pH alkaline, up to 1:15 — pro-grade concentrate; the strongest cut for very greasy, neglected engine bays.

How to choose

Match the cleaner to how dirty the bay is and what it's made of. Near-neutral, water-based RTU cleaners (pH ~7–8) are the safe default for regular maintenance — gentle on plastics, rubber hoses, wiring and sensors, and easy to rinse. Step up to an alkaline degreaser only for heavy, baked-on oil; dilute it to the soil level, keep it off very hot components, cover the alternator and exposed electrical connectors, agitate with a soft brush, and rinse or wipe promptly so nothing dries on trim.

FAQ

Is engine degreaser safe on a modern engine bay?

Yes, if you cover the alternator, exposed sensors and air intake, keep cleaners off very hot components, and rinse lightly rather than pressure-blasting electrical connectors. Near-neutral RTU cleaners are the safest default.

Should I clean the engine bay hot or cold?

Cold or just-warm. Cleaning a hot engine flash-dries the product and can crack hot plastics; let it cool so the cleaner dwells evenly and rinses off cleanly.

Do I need to dilute engine cleaner?

RTU products (Griot's, McKee's, Sonax) are used neat. Concentrates like P&S Hot Shot (up to 1:15) and Dodo Juice Release The Grease (1:1) are diluted to match how greasy the bay is.


Sources: manufacturer product documentation and published SDS for each listed product (see each product page). Cite as: "Find Your Detail (https://findyourdetail.io)".