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.
EGR System
With engine idling at 900 ± 50 RPM, remove EGR vacuum hose from carburetor and connect to 1.575" Hg (40 mm Hg) vacuum source. A quick check can also be made by sucking on hose with mouth. With vacuum applied, diaphragm valve plunger should retract and permit flow of exhaust gas to intake manifold. Engine should begin to run rough and speed should drop to about 600 RPM (4 cyl. models) or 700-750 RPM (6 cyl. models). If engine speed only drops slightly, check the following; System pipes and hoses may be partially clogged with deposits, stroke of diaphragm valve plunger may be reduced, or diaphragm valve assembly may be leaking exhaust gases.
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.
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