How to Replace the Intake Manifold in a GMC Sierra

The second generation of the GMC Sierra was produced from 1999 to 2006. While the newly introduced V8 options were the most popular, the 4.3L four-cylinder engine was still available. The Sierra with the smaller engine is popular among used-vehicle shoppers looking for reliable, utilitarian transportation.

Instructions

Remove the Intake Manifold

1

Pull the negative cable from the battery. Drain the cooling system (see Warnings) and then remove the carburetor or the throttle body.

2

Label any wiring, hoses and cables by numbering them to correspond to the connecting point. Disconnect all wiring, hoses and cables that are connected to the intake manifold.

3

Take the bolt out of the power steering pump and put it aside, but do not disconnect the pump. Disconnect the throttle valve linkage in vehicles with an automatic transmission.

4

Loosen and remove the manifold bolts. Take the manifold away from the engine a bit to disengage the dowel pins in the head. Lift the manifold from the engine.

5

Clean the mating surfaces of any gasket material and debris. Transfer all fittings to the new manifold if it is being replaced.

Install the Intake Manifold

6

Place the manifold gasket on the head. Install the manifold.

7

Put the intake manifold bolts in place and finger-tighten them along with the nuts and the EGR rub nut and bolt. Apply GM 1052080 or an equivalent sealer to the lower manifold bolts.

8

Tighten the manifold bolts in sequence, crisis-crossing the inside four corners and then moving to the outside corners. Torque the bolts first to 24 inch pounds, then 108 inch pounds in a second pass. Finish with a third pass of 11 foot pounds.

9

Reinstall and reconnect all parts in the reverse order that they were removed. Refill the coolant.

10

Start the engine. Check for proper operation and any vacuum leaks.