2004 Buick Regal

The 2004 Buick Regal is a mid-size sedan known for its comfortable ride and spacious interior. Engine options included a 3.8L Series II V6 engine, producing around 200 horsepower and 225 lb-ft of torque. A supercharged 3.8L V6 was also available with more horsepower and torque. All models came with a 4-speed automatic transmission. Owners often appreciate the Regal’s smooth ride and reliability, while some criticisms include its somewhat dated styling and average fuel economy.

Engine

3.8L Series II V6

• Intake Manifold Gasket Failure
  • Description/Symptoms: Coolant leaks, overheating, white smoke from the exhaust, loss of coolant, and sometimes rough running. This is a very common issue on the Series II 3800 V6.
  • Solution: Replace the upper and lower intake manifold gaskets with updated versions made from improved materials (often metal-framed gaskets).
  • Estimated Cost to Fix: $300 - $600
• Coolant Elbow Leak
  • Description/Symptoms: Coolant leak near the water pump and alternator area. The original plastic coolant elbows become brittle and crack over time, leading to coolant loss.
  • Solution: Replace the plastic coolant elbows with upgraded aluminum elbows.
  • Estimated Cost to Fix: $100 - $200
• Fuel Injector Failure
  • Description/Symptoms: Rough idle, misfires, decreased fuel economy, and check engine light.
  • Solution: Replace the faulty fuel injectors. May want to do all six at the same time.
  • Estimated Cost to Fix: $150 - $600+

Supercharged 3.8L Series II V6

• Supercharger Coupler Failure
  • Description/Symptoms: Rattling noise from the supercharger, loss of supercharger boost, and reduced engine performance. The nylon coupler connecting the supercharger rotors wears out over time.
  • Solution: Replace the supercharger coupler.
  • Estimated Cost to Fix: $200 - $400
• Intercooler Leak
  • Description/Symptoms: Loss of coolant, reduced supercharger performance, and possible engine overheating. The intercooler, which cools the air entering the engine, can develop leaks.
  • Solution: Replace the intercooler.
  • Estimated Cost to Fix: $400 - $800+

Transmission

4T65E 4-Speed Automatic

• Torque Converter Clutch (TCC) Failure
  • Description/Symptoms: Shuddering or vibration during light acceleration at highway speeds, erratic shifting, and possible stalling.
  • Solution: Replace or rebuild the torque converter. In some cases, a software reflash might help initially but rarely resolves the problem long-term.
  • Estimated Cost to Fix: $800 - $2000+
• Pressure Control Solenoid Failure
  • Description/Symptoms: Harsh or delayed shifting, erratic shifting, and transmission slipping.
  • Solution: Replace the pressure control solenoid.
  • Estimated Cost to Fix: $200 - $500

Suspension

• Strut Mount Failure
  • Description/Symptoms: Clunking noises from the front or rear suspension, especially when going over bumps. Worn strut mounts can also affect alignment.
  • Solution: Replace the strut mounts. It is best to replace in pairs.
  • Estimated Cost to Fix: $200 - $500
• Sway Bar Link Failure
  • Description/Symptoms: Rattling or clunking noises from the suspension when driving over bumps or turning.
  • Solution: Replace the sway bar links. It is best to replace in pairs.
  • Estimated Cost to Fix: $100 - $300

Electrical

• Window Regulator Failure
  • Description/Symptoms: Window moves slowly or not at all, grinding noises when operating the window.
  • Solution: Replace the window regulator.
  • Estimated Cost to Fix: $200 - $400
• Ignition Switch Failure
  • Description/Symptoms: Car will not start, intermittent electrical issues, car shuts off while driving.
  • Solution: Replace the ignition switch.
  • Estimated Cost to Fix: $150 - $400
• ABS Sensor Failure
  • Description/Symptoms: ABS light illuminated on the dashboard, loss of ABS functionality, and possible issues with traction control.
  • Solution: Replace the faulty ABS sensor.
  • Estimated Cost to Fix: $100 - $300

Exterior

• Rust on Rocker Panels and Lower Doors
  • Description/Symptoms: Visible rust formation on the lower sections of the body, particularly the rocker panels and lower door edges. This is common in areas with road salt.
  • Solution: Repair or replace rusted panels. This could involve welding in new metal or using body filler.
  • Estimated Cost to Fix: $500 - $2000+ depending on severity.

Interior

• Headliner Sagging
  • Description/Symptoms: The fabric headliner begins to detach from the roof and sag down.
  • Solution: Replace the headliner.
  • Estimated Cost to Fix: $200 - $500

Summary: The 2004 Buick Regal, while generally reliable, has some common issues. Intake manifold gasket and coolant elbow leaks are common on the 3.8L V6, while the supercharged version can suffer from supercharger coupler and intercooler problems. The 4T65E transmission can experience torque converter clutch and pressure control solenoid failures. Suspension issues include strut mount and sway bar link failures. Electrically, window regulators and ABS sensors are prone to failure. Rust can also be a concern, especially in areas with road salt. The severity of these issues ranges from minor to major repairs, with costs varying accordingly.