You apparently have to use new bolts with lockpatch. I'm sure somebody here has tried to re-use the bolts after cleaning and a little threadlocker (You didn't hear that from me.
Be careful with some types of threadlocker and aluminum!
I would likely put new manifold seals in if I were doing mine. I figure once and done.
From the SM:
The intake manifold is made of a composite material with the runners tuned to give the best balance of power and torque. The manifold uses a single plane sealing system and separate PCV port seals to prevent leaks. The screws connecting the manifold to the head use a thread lock patch, and must be replaced when the manifold is serviced.
1. Disconnect negative cable from battery (4).
2. Remove air cleaner assembly (Refer to 09 - Engine/Air Intake System/BODY, Air Cleaner - Removal) .
3. Disconnect electrical connectors and reposition harness.
4. Disconnect vacuum lines.
5. Perform fuel pressure release procedure(Refer to 14 - Fuel System/Fuel Delivery - Standard Procedure) .
6. Remove intake manifold retaining fasteners.
7. Remove intake manifold.
NOTE: There is NO approved repair procedure for the intake manifold. If severe damage is found during inspection, the intake manifold must be replaced.
Before installing the intake manifold thoroughly clean the mating surfaces. Use a suitable cleaning solvent, then air dry.
1. Inspect the intake sealing surface for cracks, nicks and distortion.
2. Inspect the intake manifold vacuum hose fittings for looseness or blockage.
1. Install intake manifold seals (1,3).
2. Position intake manifold (2) in place.
3. Install new intake manifold bolts (with thread lock patch) and tighten to 12 N•m (105 in. lbs.) in the sequence shown.
4. Position wiring harness in place and connect electrical connectors.
5. Connect fuel line.
6. Connect brake booster and vacuum hoses.
7. Install air cleaner assembly (Refer to 09 - Engine/Air Intake System/BODY, Air Cleaner - Installation) .
8. Connect negative battery cable.