Hyundai Tucson: Emission Control System / Crankcase Emission Control System

Description and Operation

- Description

A : Crankcase pressure regulating valve (PRV)
B : Breather hose
C : Intake hose
D : Air flow
E : Intake manifold
F : Cylinder block

① Blow-by gas flow② Blow-by gas inflow to the cylinder head cover throungh the cylinder block & head & chain cover③-1 In the partial load area, blow-by gas inflow to the intake manifold through the PRV valve which in the head cover.③-2 In the full load area, blow-by gas inflow to the intake hose through the PRV valve which in the head cover.④ Mix of intake hose and blow-by gas. Blow-by gas is circulated by the ③-1, ③-2 procedure.⑤ Combustion the air-flow mixture.⑤-1 Air flow to cylinder block.

Positive Crankcase Ventilation (PCV) Valve

- Description Pressure Regulating Valve (PRV) is installed to prevent the over pressure of combustion gas through the piston ring and onto the crankcase.

- Operating Principle

Engine condition	Stop	Idle or Deceleration	Normal operating condition	Accelerating in the high load area
Intake manifold pressure	0	High	Appropriate	Low
PRV (Diaphragm)	Full open	A little open	Appropriate open	Considerable open
Amount of blow-by gas	0	A little	Middle	A lot
Diaphragm component part

- Removal

1.Remove the cylinder head cover.Refer to Engine Mechanical System - "Cylinder Head Cover")

- Installation

1.Install in the reverse order of removal.

Crankcase Check Valve

- Removal and Installation

   

• Be careful not to damage the parts located under the vehicle (floor under cover, canister, fuel tank) when raising the vehicle using the lift.(Refer to General Information - "Lift and Support Points")

1.Disconnect the battery (-) terminal.

2.Remove the engine room under cover.(Refer to Engine And Transaxle Assembly - "Engine Room Under Cover")

3.Remove the drive belt.(Refer to Drive Belt System - "Drive Belt")

4.Remove the compressor mounting bolts.(Refer to Heating, Ventilation and Air Conditioning - "Compressor")

5.Disconnect the crankcase check valve hose (A) and then remove the crankcase check valve (B).

Tightening torque : 9.8 - 11.8 N.m (1.0 - 1.2 kgf.m, 7.2 - 8.7 lb-ft)

   

• Push the check valve to the end of the mounting surface, and then tighten the bolt.