Kia Optima Hybrid: Evaporative Emission Control System / NVLD(Natural Vacuum Leakage Detection) Repair procedures

Removal
1.
Turn the ignition switch OFF and disconnect the battery negative (-) terminal.
2.
Disconnect the NVLD connector (A).
3.
Disconnect the ventilation hoses (B,C).

4.
Remove the NVLD after by loosening the bolts (A).

Installation
Install the component with the specified torques.
Note that internal damage may occur when the component is dropped.
If the component has been dropped, inspect before installing.
1.
Install in the reverse order of removal.

NVLD mounting bolt:
2.3 ~ 3.3 N.m (0.2 ~ 0.3 kgf.m, 1.7 ~ 2.5 lb-ft)

Inspection
[Mechanical inspection]
1.
Turn ignition switch OFF.
2.
Disconnect the NVLD connector.
3.
Remove the NVLD.
4.
Connect the hose (A) to the canister hose connected port as below.
5.
After immersing the hose (A) in water, Apply more than 6 mbar (positive) pressure to Atmosphere port (B).
6.
If the NVLD is normal, many bubbles will indicate large leak.
   
Allowable internal leakage of 0.35 g/hr at 3 mbar will show as one bubble every second (approximately).

[Electrical inspection]
1.
Connect power supply line and ground line to the NVLD terminals as below.
2.
Measure current between the NVLD terminal 1 and battery (+) terminal during NVLD switch open.
3.
Measure current between the NVLD terminal 1 and battery (+) terminal during NVLD switch closed.
4.
Measure current between the NVLD terminal 2 and battery (+) terminal during NVLD switch open.
5.
Check the current is within the specification.
   
NVLD switch is normal open.
When applying more than 6 mbar (Positive) pressure to canister port, switch is closed.

NVLD(Natural Vacuum Leakage Detection) Schematic Diagrams

Circuit Diagram ...

Exhaust Emission Control System

...

Other information:

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Fluid Components and Components Location


Component Location 1. ATF fill hole (eyebolt) 2. ATF level plug3. ATF drain plug ...

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Troubleshooting


Troubleshooting SymptionSuspect areaRemedyEngine misfire with abnormal internal lower engine noises.Worn crankshaft bearingsLoose or out of specification engine flywheelReplace the crankshaft and bearings as required.Repair or replace the flywheel as required.Worn piston rings(Oil consumption may or ...

© 2025 Copyright www.koptimatfhev.com