Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Vacuum RESTRICTOR
Orifice type flow restrictor is used in emission calibrations to control flow rate and/or timing inactions. Restrictor can be found in EGR valve system (opening and closing), part throttle spark advance, purge system and thermactor system. Flow rate through restrictor is same in both directions. If blocked, replace restrictor.
| Color | Hole Size In. |
|---|---|
| Blue | .015 |
| Red | .020 |
| Orange | .024 |
| Yellow | .030 |
| Green | .050 |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.