Yes, they are Direct Injection engines. Spec sheet for RPO code "LLT" engine below (as taken from GM Powertrain site):
2009 GM 3.6L V-6 VVT DI ( LLT ) 060608
Type: 3.6L V-6
Displacement: 3564cc ( 217 ci )
Engine Orientation: L= Longitudinal T=Transverse L
Compression ratio: 11.3:1
Valve configuration: dual overhead camshafts
Valves per cylinder: 4
Assembly site/s: St. Catharines, Ontario
Flint Engine South, Flint Mi.
Ramos Arizpe, Mexico
Melbourne, Australia
Valve lifters: roller follower with hydraulic lash adjusters
Firing order: 1-2-3-4-5-6
Bore x stroke: 94 x 85.6 mm
Bore Center ( mm ) 103
Fuel system: DI
Fuel Type: Regular Unleaded
Applications: Horsepower: hp ( kw )
Cadillac CTS 304 hp ( 227 kw ) @ 6400 rpm SAE CERTIFIED
Cadillac STS 302 hp ( 225 kw ) @ 6300 rpm SAE CERTIFIED
Saturn Outlook ( with dual exhaust ) 288 hp ( 215 kW ) @ 6300 rpm SAE CERTIFIED
Saturn Outlook ( with single exhaust ) 281 hp ( 210 kW ) @ 6300 rpm SAE CERTIFIED
GMC Acadia ( with dual exhaust ) 288 hp ( 215 kW ) @ 6300 rpm SAE CERTIFIED
Buick Enclave ( with dual exhaust ) 288 hp ( 215 kW ) @ 6300 rpm SAE CERTIFIED
Chevrolet Traverse ( with dual exhaust ) 288 hp ( 215 kW ) @ 6300 rpm SAE CERTIFIED
Chevrolet Traverse ( with single exhaust ) 281 hp ( 210 kW ) @ 6300 rpm SAE CERTIFIED
Applications: Torque: lb-ft. ( Nm )
Cadillac CTS 273 lb-ft ( 370 Nm ) @ 5200 rpm SAE CERTIFIED
Cadillac STS 272 lb-ft ( 369 Nm ) @ 5200 rpm SAE CERTIFIED
Saturn Outlook ( with dual exhaust ) 270 lb-ft ( 366 Nm ) @ 3400 rpm SAE CERTIFIED
Saturn Outlook ( with single exhaust ) 266 lb-ft ( 361 Nm ) @ 3400 rpm SAE CERTIFIED
GMC Acadia ( with dual exhaust ) 270 lb-ft ( 366 Nm ) @ 3400 rpm SAE CERTIFIED
Buick Enclave ( with dual exhaust ) 270 lb-ft ( 366 Nm ) @ 3400 rpm SAE CERTIFIED
Chevrolet Traverse ( with dual exhaust ) 270 lb-ft ( 366 Nm ) @ 3400 rpm SAE CERTIFIED
Chevrolet Traverse ( with single exhaust ) 266 lb-ft ( 361 Nm ) @ 3400 rpm SAE CERTIFIED
Fuel shut off: 6950 rpm
Engine Mass (kg/lbs) engine plant as shipped weight 172 / 380 (estimate) automatic CTS and STS
194 / 428 (estimate) manual CTS and STS
164 / 361 (estimate) Outlook, Acadia, Enclave, Traverse
Emissions controls: evaporative system
dual catalytic converters
positive crankcase ventilation
MATERIALS
Block: sand cast aluminum (319) with cast in iron bore liners
Cylinder head: cast aluminum ( 319 semi permanent mold )
Intake manifold: aluminum ( 319 Upper, and Lower )
Exhaust manifold: high-silicon moly cast iron
Main bearing caps: sintered steel ( CU infiltrated )
Crankshaft: forged steel ( 1038 V )
Camshaft: cast nodular iron
Connecting rods: sinter forged steel
Additional features: Four-cam continuously variable cam phasing
Internal exhaust gas recirculation ( EGR )
Pressure-actuated piston cooling jets
Torque-based engine management system
Secondary throat cut inlet ports
Direct injection fuel system
High-pressure, engine-driven fuel pump with stainless steel fuel rails
Internal front cover damper plates
Cartridge style oil filter
Extended life spark plugs
Extended life coolant
Extended life accessory drive belts
7.7mm IT chain system for all HFV6 applications
Coil-on-plug ignition
Structural cast-aluminum oil pan with steel baffles
5W30 GF4 Mineral Oil
Synthetic Oil for Cadillac applications