CarCareTruth Score
Decent, but it's tough on the environment.
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Prices may varyThe manufacturer's Safety Data Sheet classifies this product with one or more GHS Category 1 health hazards — the most severe tier. The hazard statements in quotes below are the verbatim GHS language from the SDS, as required by OSHA's Hazard Communication Standard. The line under each statement translates the GHS classification into plain language.
GHS Category 1 aspiration toxicity — thin, oily liquids can slip into the lungs if swallowed, causing chemical pneumonia.
GHS Category 1 reproductive toxicity — classified as suspected of damaging fertility or harming an unborn child.
If swallowed, inhaled, or splashed in eyes:
Call Poison Control immediately at 1-800-222-1222 (US, 24/7, free) and have the product container with you. Poison Control's standing guidance is to not induce vomiting after chemical exposure; they will direct first-aid steps based on the specific product.
About this product's hazards. This product's Safety Data Sheet uses signal word danger. Read the manufacturer's SDS and follow all safety instructions before use. CarCareTruth ratings translate the manufacturer's safety sheet. They do not replace the SDS or substitute for a hazard assessment specific to your task.
Health score is for adult use as intended, per the manufacturer's SDS. It does not model child ingestion, accidental spill cleanup, or off-label use. See the safety panel below for full hazard classification, and /disclaimer for the full editorial scope.
GHS hazard codes are quoted from the manufacturer’s Safety Data Sheet. PPE tiers below translate those codes and the listed ingredient chemistry; they are not CarCareTruth recommendations.
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From the manufacturer’s Safety Data Sheet, Section 8
“SDS Section 2 classifies the MAF cleaner with H319 (Serious Eye Irritation Cat 2A). Aerosol mist at face level during engine-bay work can reach the eyes. SDS Section 8 specifies eye protection.”
— CRC
U.S. regulatory standard
29 CFR 1910.133(a)(1)
“The employer shall ensure that each affected employee uses appropriate eye or face protection when exposed to eye or face hazards from… liquid chemicals…”
ANSI Z87.1 (incorporated via §1910.6)
OSHA standards apply to workplaces. Cited here as the U.S. reference threshold for the underlying hazard class.
CarCareTruth publishes the cited sources verbatim and does not advise what action a user should take. Consult the full SDS before use.
From the manufacturer’s Safety Data Sheet, Section 8
“SDS Section 2 classifies Skin Irritation Cat 2 (H315). The petroleum distillate solvent base in the MAF cleaner warrants chemical-resistant gloves, particularly with repeated handling across a 6-pack case.”
— CRC
U.S. regulatory standard
29 CFR 1910.138(a)
“appropriate hand protection when employees' hands are exposed to hazards such as those from… chemicals which produce an adverse effect on the skin or eyes…”
OSHA standards apply to workplaces. Cited here as the U.S. reference threshold for the underlying hazard class.
CarCareTruth publishes the cited sources verbatim and does not advise what action a user should take. Consult the full SDS before use.
From the manufacturer’s Safety Data Sheet, Section 8
“DANGER signal word on the MAF cleaner is driven by health H-codes (H304 aspiration hazard, H360 reproductive toxicity, H370 STOT-SE Cat 1), not flammability alone. Aerosol at close range in the engine bay, combined with high vapor pressure, means SDS §8 calls for adequate ventilation and respiratory protection in poorly ventilated spaces.”
— CRC
U.S. regulatory standard
29 CFR 1910.134; 1910.138; 1910.1000
“the primary objective shall be to prevent atmospheric contamination… When effective engineering controls are not feasible… appropriate respirators shall be used.”
OSHA standards apply to workplaces. Cited here as the U.S. reference threshold for the underlying hazard class.
CarCareTruth publishes the cited sources verbatim and does not advise what action a user should take. Consult the full SDS before use.
The published Safety Data Sheet for this product does not specify ventilation protection for consumer use.
Workplace context
29 CFR 1910.134(a); 1910.1000
“the primary objective shall be to prevent atmospheric contamination [via] accepted engineering control measures (for example, enclosure or confinement of the operation, general and local ventilation…).”
Triggered by GHS H336 on the SDS.
OSHA standards apply to workplaces. Cited here as the U.S. reference threshold for the underlying hazard class.
PPE tiers translate the manufacturer’s SDS and U.S. regulatory standards. Not professional safety advice. How we report safety.
This product ranks #2 of 5 in MAF Sensor Cleaner.
Last reviewed July 5, 2026
TL;DR A bulk case of CRC's popular MAF sensor + throttle body cleaner twin pack · 6 twin packs, 12 cans total. The MAF cleaner's DANGER signal word is driven by health H-codes (H304 aspiration hazard, H360 reproductive toxicity), not just flammability · higher hazard than simpler aerosol cleaners. Wear goggles and gloves; use with the garage door open.
Each twin pack pairs a MAF sensor cleaner can with a throttle body cleaner can. For the MAF cleaner: remove the sensor, two to four straw-directed bursts at the element, air-dry a couple minutes before reinstalling. For the throttle body cleaner: spray directly into the bore with the engine off. The MAF cleaner evaporates completely without residue · community data from the widely sold standalone can, corroborated by BITOG forum threads, confirms codes stay cleared on hot-wire and hot-film sensors. The case format suits anyone doing this maintenance across multiple vehicles or over several years, since each twin pack is single-use.
The right buy for a home mechanic who wants several MAF-and-throttle-body cleaning sessions on hand at a lower per-session cost than buying single twin packs repeatedly. Skip it if you only need one cleaning session (the single twin pack is the better buy), or if you're in California, since the MAF cleaner component is not confirmed CARB compliant.
The MAF cleaner drives this product's hazard profile: DANGER from health H-codes · H304 aspiration hazard, H360 reproductive toxicity, H370 STOT-SE Cat 1 · not flammability alone. The retail box itself prints this DANGER warning on the front panel. Prop 65 is confirmed on the MAF cleaner component. Goggles, gloves, and open-garage or outdoor use are the chemistry-based minimum. The throttle body cleaner is also DANGER-classified but at lower severity. Environmentally, the MAF cleaner is not confirmed CARB compliant, carries H411 aquatic toxicity, and has no biodegradability data on file.
Each of the 6 twin packs contains one can of CRC Mass Air Flow Sensor Cleaner and one can of CRC Throttle Body & Air-Intake Cleaner · 12 cans total. This is a bulk case of the same twin pack CRC sells individually.
The MAF sensor cleaner is the lead and dominant component · it's named first on the box, carries the higher hazard profile (petroleum distillate formula with DANGER from health H-codes), and drives this product's scoring. Neither component's label or SDS makes an explicit O2-sensor-safe or catalytic-converter-safe claim, which is the threshold the throttle-body-cleaner category requires.
The MAF cleaner component's DANGER signal word is driven by health H-codes in SDS Section 2, specifically H304 (aspiration hazard), H360 (reproductive toxicity Cat 1A from methanol), and H370 (STOT-SE Cat 1). This is a meaningful distinction from aerosols that carry DANGER only from flammability.
Yes · on the MAF cleaner component. SDS Section 15 lists ethylbenzene, methanol, toluene, and n-hexane under Prop 65. The throttle body cleaner component also carries a Prop 65 warning per its own SDS.
6 twin packs means 6 separate MAF-and-throttle-body cleaning sessions · a lower per-session cost than buying the single twin pack repeatedly, since the buy box shows current per-unit pricing.
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