https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagef458952c2a4d48fa8299c4f50b2e07d1.txt

<h2>What is a secondary air injection check valve?</h2>The role of a secondary air injection check valve is to prevent the reverse flow of exhaust gases into the Secondary Air Injection (SAI) system, particularly during specific engine conditions like cold starts.When a vehicle's engine is cold, the secondary air injection check valve produces higher emissions. The SAI system is designed to reduce these emissions by introducing fresh air into the exhaust system during cold starts. The Secondary Air Injection Check Valve is like a one-way door in this system. It ensures that only fresh air, provided by the SAI pump, is allowed into the exhaust manifold. This fresh air helps burn any unburned hydrocarbons in the exhaust, lowering emissions. The check valve's critical job is to prevent exhaust gases from flowing backward into the SAI system. This would disrupt the emission-reducing process and potentially lead to higher pollution levels.<h2>How do I know if my&nbsp;secondary air injection check valve&nbsp;is bad?</h2>Some common signs that can indicate a bad SAI check valve:<ul><li>Check engine light: Illumination of the check engine light on the dashboard, often accompanied by specific error codes related to the SAI system.</li><li>Increased emissions: Higher emissions levels, potentially leading to failed emissions tests.</li><li>Poor cold start performance: Rough or problematic cold starts, including rough idling and hesitation.</li><li>Reduced fuel efficiency: Decreased gas mileage, resulting in fewer miles per gallon.</li><li>Unusual engine noises: Odd sounds like hissing or rattling may emanate from the SAI system.</li><li>The smell of unburned fuel: The presence of the smell of unburned fuel in the exhaust, is noticeable from the tailpipe.</li><li>Loss of engine power: Possible reduction in engine power, especially during acceleration.</li></ul>

Secondary Air Injection Check Valve

Air Cleaner

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagecfb361ff6cc54b22b1f30236d8cb84ae.txt

Air Filter Box

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageef32df7428f2425b87301667c1ec9bd3.txt

Mass Air Flow Sensors/Car MAF Sensors | A-Premium

Air Flow Sensor

Air Intake Duct

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image172ed642cd5649409681f03dd9cb3946.txt

Air Intake Hose

Air Intake Manifold Actuator Control Solenoid

Air Intake Manifold Flap Adjuster

Air Intake Manifold Runner Control Sensor

Air Intake Resonator

Electric Vacuum Pump

Engine Air Duct Assembly

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image209fc8ff3521428080a60d3b94252f31.txt

Engine Air Filter

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image0a94f36fd961461aa4c6e7d9631359f8.txt

Intake Manifold

Intake Manifold Flap Actuator

Intake Manifold Repair Bracket

Intake Manifold Runner Control Valve

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagea8dd964331f6410bbb12b303bd28806f.txt

Intercooler

Intercooler Hose

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image36d1a21a946c40cd88807cac4f16802c.txt

Oxygen Sensor

Car Oxygen Sensor Price From $24.99 | A-Premium

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image2874032448264cc89fcfd3d32e8c4bd4.txt

Pressure Sensor

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image22759bb496ff466483e3cb52fcdbc26f.txt

Supercharger Pulley Drive Unit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageaa46cde230574820aa9d24be234f1d48.txt

Supercharger Snout Rebuild Kit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image71b6637412454ac48505f8fe656d59da.txt

Throttle Body

Throttle Cable

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image95a81ec8105e4580ac078f34b15f7105.txt

Throttle Position Sensor

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagecff91ba9de7c4cb1932d544e82f0bf52.txt

Turbocharger

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image5e2ee31f66ee40b392e6f7f562f3540e.txt

Turbocharger Gasket Kit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagedbb3e2f10990462aa8dbd76eb04c2e54.txt

Turbocharger Oil Line

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image73f58f2321b2459fb6919729a345e546.txt

Vacuum Pump

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagec297244633284630939f3bdf6d50529b.txt

Air Filters & Intake Systems

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image72a54af151ea46ae9a947a6c57ba4aae.txt

Camshaft Adjuster

Camshaft Adjuster Cover

Camshaft Kit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image0c746ef912ad473cb3d80560a2d7e0a5.txt

Camshaft Timing Gear

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageac12d53c77414db58a69179123e8d9a5.txt

Camshafts

Chain Tensioner Adjuster

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image98db53590892414c857477e118cb5bca.txt

Cylinder Head

Cylinder Head Assembly

Eccentric Shaft Actuator

Engine Timing Belt

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagecd9a40b4eb4546c08e376fe1b7fe5819.txt

Engine Valve Cover

Engine Valve Cover Gasket

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagec9ce5895dea14f089b6df8f067fd618b.txt

Harmonic Balancer

Rocker Arm

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image2b16cd32bbf04245b2d4ffd4da2474f3.txt

Rocker Arm Shaft Lifter Assembly

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image04246ffa3e3a4cca9c49011214ff6a6f.txt

Timing Belt Kit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagea2df7008626b4434a4a343dc1aba16eb.txt

Timing Chain Gear

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageeeb3265558bd478fbac20059ec555c8c.txt

Timing Chain Kit

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image5af48eb273014fb5a489fe6bb5d14c1e.txt

Timing Cover

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image77c0478f7034493f91708786ed8fc52c.txt

Timing-Control Valve Solenoid

Valve Cover Gasket

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageba0bae7f90e346a288aae78753a2f3a0.txt

Valve Lifter Guides

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageff7f4b3ee7204c2d93e5d7f67976617f.txt

Valve Lifters Tappet

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image4ed51fbea7bc4818aa193ac0256a2f42.txt

Cams, Timing & Valvetrain

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image7e54d40a14d3470cb6c0e1820c263b93.txt

Belt Tensioner

Coolant Level Sensor

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagea688717671d94972a2a5a846db2a97c6.txt

Crank Installer Tool

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageef7c9a21b8f3481fafd9dc34deefd95e.txt

Crankcase Breather Hose

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image9a51da7735e648caa411dd19fe3015c6.txt

Crankcase Breather Valve

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image0f26e0448a8b4d72a06bbefb2c03ab27.txt

Crankshaft Position Sensor

Crankshaft Pulley

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagedbfa702977844f27a12938e2f7f0545f.txt

Engine Oil Dipstick

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image69a46fdd403d4aee988b03c7ce172cb1.txt

Engine Oil Dipstick Tube

Engine Oil Filter

Engine Oil Pan Gasket

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagea7c063be923740da92163da876f8499f.txt

Flywheel

Harmonic Balancer Crankshaft Hub

Knock Sensor

Oil Baffle

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image850df044e5234274b30aa010ee94dba5.txt

Oil Cooler

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageebaf93bfb7c046d789a04bb0ac166235.txt

Oil Cooler Line

Oil Drip Pan

Oil Filler Cap

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image0a064858e22c4a7ba148c91978e1e5a8.txt

Oil Filter

Oil Filter Base

Oil Filter Cover

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image32b3ec52ad0249e58ed4ae5303d2f0e7.txt

Oil Filter Housing

Oil Filter Housing Cover

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagedef8d67a5f484cb2a2d594d50eb5b73a.txt

Oil Level Sensor

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagee113aaa2222d49448a25eb9c355123e1.txt

Oil Pan

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagec53c3f4f8470449caa2c14852afab4e6.txt

Oil Pump

Oil Pump Drive Gear Shaft

Oil Pump Pickup Tube

Oil Separator

Serpentine Belt

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image650cc271414d4f718467813be1c4a882.txt

Cranks, Pistons, Oil & Components

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image5e4e697a02574c87ae0b5cfda83cd3e8.txt

Camshaft Position Sensor

Camshaft Position Sensor & Magnet Kit

Connector Plug

Distributor Cap

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image746c8a47c1aa4355b9491943978d5676.txt

Electronic Ignition System

Engine Valve Covers & Ignition Coils Kits

Glow Plug

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagec81e856f9df545e6a9f4b11411937f3d.txt

Glow Plug Relay Module

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image74cc3f1efb2d492684aac85a1f3bd96f.txt

Ignition Coil

Ignition Coils & Spark Plugs & Wires Kits

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image57ca3e4e8038449ab08157e98602f20b.txt

Ignition Coils & Spark Plugs Kits

Ignition Coils & Wires Kits

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image41d187d382d941e79a6cde28a906b960.txt

Ignition Distributor

Ignition Lock Cylinder

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagedf6ffde1de044334b7320f4e47bcd934.txt

Ignition Starter Switch

Ignition Switch Actuator

Kill Switch

Knock Detonation Sensor

Relay

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image50b27b80d8bb4caa97e9d3e5826bee31.txt

Spark Plug

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image27a6097036004160abe4de68c69ffa5c.txt

Spark Plug Wire

Electronic Control Modules, Ignition & Distributors

Engine Wiring Harness

Intake Manifold Repair Kit

Pulley

Engine Components & Accessories

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imageffda8e886b1944fba7d4f9a8ee0cc9ea.txt

Active Grille Shutter Actuator

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image1bcab546ad734695ae275b9f5387598a.txt

Auxiliary Water Pump

Drive Motor Inverter Cooler

Electric Engine Water Pump

Engine Coolant Air Bleeder Valve

Engine Coolant Pipe

Engine Coolant Shut Off Valve

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image134c67bba50247a988314c79d505b0d6.txt

Expansion Tank

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagefc43366b4109446c870f3055074a7e71.txt

Expansion Tank Mounting Plate

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image3470d27a460a40229f3cb464f0d6e426.txt

Fan Pulley Bracket

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imaged8199a7345cc43e88a5d14ecfb40b3a2.txt

Fuel Cooler

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image5e7de284a6cb4201b9df2ae5ec1b8a96.txt

Overflow Hose Connector

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image8ddda567a60c477c9a65cf6cdae4c553.txt

Radiator

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/image2760208548f5456e9cc9bf5074dd18c6.txt

Radiator Control Fan Module

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagebef86b916787420493e074f7f0a5b4fb.txt

Radiator Core Support Skid Bar Plate

Radiator Fan Cooling Motor

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imagee5529da684c54cf9bfe4c53e51d23532.txt

Radiator Hose

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imaged782e20933d346be8c825ba03dacd7a2.txt

Engine Cooling

https://yt-prod-media-assets.s3.us-east-2.amazonaws.com/2022/item/description/imaged5cb3019fd234fd5aad60f2d16b57d5e.txt

The engine comprises many essential elements such as the lower cylinder block, upper cylinder head(s), and the cooling & lubricating systems. With A-Premium aftermarket engine components, you can expect that your engine deliver years of reliable performance. We offer a diverse selection of engine components from air filters and ignition coils (kits) to fuel pumps to cater to your needs.

2017 Toyota 4Runner Secondary Air Injection Check Valve

Shop By Toyota Years