NEW OR CHANGED 3800 Series II Supercharged 3.8L V-6 (L67) 2004 Model Year Summary
· New Application in Chevrolet Impala and Monte Carlo
· Powdered Metal Connecting Rods
· Ultra-Fast Oxygen Sensors
· PO4+ Powertrain Control Module
· Direct-Mount Air Conditioning Compressor for Impala and Monte Carlo
· Improved Sealing
· Improved Accessory Belt
· Improved Starter
· 5W-30 Engine Oil
· Changes for Common Assembly with new Series III V-6
FULL DESCRIPTIONS OF NEW OR CHANGED FEATURE
NEW APPLICATION IN CHEVROLET IMPALA AND MONTE CARLO
The supercharged 3800 Series II SC will be offered as an option in the 2004 Chevrolet Impala and Monte Carlo. The Series II is no longer available in the Pontiac Grand Prix, which is equipped with the new 3800 Series III (RPOs L26 and L32) for model year 2004
POWDERED METAL CONNECTING RODS
The 3800 Series III has new hot-forged powdered metal connecting rods. Powdered metal is more durable and reliable than conventional cast iron, delivering greater anticipated life. As importantly, the powdered metal rods are
stiffer than the cast iron parts they replace. That increases the resonant frequency of the rod and translates to lower vibration amplitude, meaning an overall increase in engine smoothness.
ULTRA-FAST OXYGEN SENSORS
Oxygen sensors on the 3800 Series II SC have greater heating capacity – 8.5 watts for the front sensor and 7.5 watts for the rear, compared to 6 watts in 2003. Increased wattage allows the sensors to achieve their most efficient operating temperature more quickly. The new sensors are also pulse-width modulated, allowing the PCM to manage them at variable heating rates, rather than with a basic on-off switch.
The oxygen sensors are located where the exhaust manifold runners meet, before the catalytic converter in the engine's exhaust stream, and after the catalytic converter in the exhaust pipe. In effect, they measure emission levels going into the catalytic converter and emission levels coming out. Using readings from both sensors, the PCM manages various engine operations in a fashion that minimizes exhaust emissions. The new ultra-fast sensors allow the exhaust system to achieve this “closed loop” operation in matter of seconds, monitoring oxygen levels before and after the catalytic converter for maximum emissions reduction.
PO4+ POWERTRAIN CONTROL MODULE
The 3800 Series II SC is managed by a new Powertrain Control Module. GM’s P04+ PCM adds software capability to manage the new oxygen sensors. Moreover, the Series II PCM is now common with that used on the GM’s 3100 and 3400 60-degree V-6 engines (RPOs LG8 and LA1). Such common parts reduce corporate inventory, streamline procurement practices and contribute to a common objective every automobile buyer understands: more efficiency in vehicle assembly plants an
