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.
1985 Cadillac Seville V8-350 5.7L DSLFACTORY OEM SERVICE PROCEDURE
Glow Plug Controller Bench Test
Fig. 7 Water in fuel system fuel level sender & water detector:
1. Remove glow plug controller from vehicle and allow to cool below 122°F.
2. Connect test equipment to controller. Refer to fig. 7 in previous section.
3. Close test switch and observe test lamps. Both lamps should immediately go on when test switch is closed. After 5-7 seconds, ``Wait'' lamp should go off, followed by the ``Glow Plug'' lamp in 35-55 seconds. After 2 minutes, both lamps should remain off.
4. Open test switch, wait several seconds, then close switch. Both test lamps should immediately go on.
5. Replace controller if operation is not as described.
Factory Service Tools
Use the Manual With the Right Hardware
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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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