1999 Pontiac Bonneville

1999 Pontiac Bonneville

The 1999 Pontiac Bonneville is a full-size sedan that was available with a choice of two engines and two transmissions. The base engine was a 3.8-liter V6 that produced 200 horsepower and 225 lb-ft of torque. The optional engine was a 3.8-liter supercharged V6 that produced 240 horsepower and 280 lb-ft of torque. Both engines were mated to a four-speed automatic transmission.

People who like the Bonneville praise its comfortable ride, spacious interior, and powerful engine options. However, some people complain about its poor fuel economy and lack of modern features.

Engine 3.8L V6

• Intake Manifold Gasket Failure
  • Description/Symptoms: Coolant or oil leaking from the intake manifold gasket, causing overheating or engine misfires.
  • Solution: Replace the intake manifold gasket.
  • Estimated Cost to Fix: $300 - $500+
  • Recalls: None Found
• Water Pump Failure
  • Description/Symptoms: Leaking coolant from the water pump, causing overheating and engine damage.
  • Solution: Replace the water pump.
  • Estimated Cost to Fix: $200 - $300+
  • Recalls: None Found

3.8L Supercharged V6

• Supercharger Bearing Failure
  • Description/Symptoms: Whining or grinding noise from the supercharger, causing reduced boost and engine performance.
  • Solution: Replace the supercharger bearings.
  • Estimated Cost to Fix: $1,000 - $1,500+
  • Recalls: None Found

Transmission 4-Speed Automatic Transmission

• Shift Solenoid Failure
  • Description/Symptoms: Transmission slipping or refusing to shift gears, causing delayed acceleration or rough shifting.
  • Solution: Replace the failed shift solenoid.
  • Estimated Cost to Fix: $300 - $500+
  • Recalls: None Found
• Transmission Cooler Line Failure
  • Description/Symptoms: Transmission fluid leaking from the cooler lines, causing overheating and transmission damage.
  • Solution: Replace the failed transmission cooler lines.
  • Estimated Cost to Fix: $200 - $300+
  • Recalls: None Found

Suspension

• Strut Mount Failure
  • Description/Symptoms: Clunking or rattling noise from the front suspension, especially when turning or hitting bumps.
  • Solution: Replace the failed strut mounts.
  • Estimated Cost to Fix: $200 - $300+ per side
  • Recalls: None Found
• Rear Shock Absorber Failure
  • Description/Symptoms: Bouncing or swaying rear end, especially when driving over bumps.
  • Solution: Replace the failed rear shock absorbers.
  • Estimated Cost to Fix: $200 - $300+ per side
  • Recalls: None Found

Electrical

• Alternator Failure
  • Description/Symptoms: Dimming lights, flickering electronics, or battery warning light illuminated.
  • Solution: Replace the failed alternator.
  • Estimated Cost to Fix: $300 - $500+
  • Recalls: None Found
• Starter Failure
  • Description/Symptoms: Engine failing to start or turning over slowly.
  • Solution: Replace the failed starter.
  • Estimated Cost to Fix: $200 - $300+
  • Recalls: None Found

Exterior

• Headlight Switch Failure
  • Description/Symptoms: Headlights not turning on or flickering.
  • Solution: Replace the failed headlight switch.
  • Estimated Cost to Fix: $100 - $200+
  • Recalls: None Found

Interior

• Power Window Switch Failure
  • Description/Symptoms: One or more power windows not functioning or working intermittently.
  • Solution: Replace the failed power window switch.
  • Estimated Cost to Fix: $100 - $200+ per switch
  • Recalls: None Found
• Climate Control Panel Failure
  • Description/Symptoms: HVAC controls not responding or displaying errors.
  • Solution: Replace the failed climate control panel.
  • Estimated Cost to Fix: $200 - $300+
  • Recalls: None Found

Summary

The 1999 Pontiac Bonneville has a number of potential issues, particularly with its engine and transmission. While some of these issues are relatively minor and inexpensive to fix, others can be quite costly. Overall, the Bonneville’s reliability is below average for its class.