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.
1990 Hyundai Excel GLS, AutomaticFACTORY OEM SERVICE PROCEDURE
Exhaust Gas RECIRCULATION (EGR) System: Notes
- Disconnect Green-striped hose from throttle body and connect hand-held vacuum pump to hose end. Plug nipple where hose was connected to throttle body. When engine is 140°F (60°C) or less and at idle, apply vacuum to disconnected hose. If idle does not change and vacuum bleeds down, system is okay.
- When engine is 158°F (70°C) or more and at idle, apply 2 inches Hg. If idle does not change and vacuum holds, system is okay.
- Using a vacuum pump, apply 6.8 inches Hg. If idle becomes unstable or engine stalls (and vacuum holds), system is okay.
Factory Service Tools
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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.