Emission Control Systems: Specifications

1991 Volkswagen Jetta L4-1984cc 2.0L DOHCSECTION Specifications


EGR VALVE
Vacuum To Open Valve 0.7 - 0.8 in. Hg

Thermostatic Air Cleaner (TAC)
Open To Warm Air 68° F (20 ° C)
Open To Cold Air 86° F (30 ° C)

Thermo-Vacuum Valve (EGR)
Valve Open Below 81° F (27° C)
Valve Closed Above 120° F (49° C)

Vacuum Amplifier (EGR)
VACUUM AT IDLE
With Tee In Red Vacuum Line 0.3 in. Hg.

AMPLIFIED VACUUM AT IDLE
With Tee In Blue Vacuum Line 1.5 - 3.5 in. Hg.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.