Removal (Federal)
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Disconnect the negative battery cables. Loosen the outlet duct clamp at the upper intake manifold cover. Remove the upper intake manifold cover from the outlet duct. Remove the upper intake manifold cover. Remove the battery supply wiring harness nut and harness connector.
- Using a flat bladed screwdriver, disengage the glow plug controller cover clips. Remove the glow plug controller cover. See Fig 1. Remove the glow plug relay terminal nuts and wires. Remove the glow plug controller retainer nuts. Lift the glow plug controller off the studs.
- Separate the glow plug relay from the glow plug controller housing by inserting a small screwdriver between them while prying the relay assembly outward. See Figure. Slide the glow plug relay outward to disengage it from the glow plug controller housing. Using a flat bladed screwdriver, disengage the glow plug relay clip. Remove the glow plug relay.