1991 Mazda Miata

Introduction:

The 1991 Mazda Miata is a sporty, rear-wheel-drive roadster that quickly gained popularity for its handling, affordability, and fun-to-drive nature. It was initially offered with a 1.6-liter inline-4 engine and 5-speed manual transmission. Later models offered a 1.8-liter inline-4 engine with various transmission options. While the Miata is generally reliable, some common issues have been reported over the years.

Engine

• 1.6-liter Inline-4:
  • Timing belt failure: The timing belt can fail prematurely, causing catastrophic engine damage. Symptoms include engine misfiring, rough idling, and loss of power. Replacing the timing belt and pulleys is the solution, typically costing $400 - $800+.
  • Head gasket failure: The head gasket can fail, causing coolant and oil to mix. Symptoms include overheating, coolant loss, and engine misfiring. Replacing the head gasket requires extensive labor and costs $1000 - $1500+.
• 1.8-liter Inline-4:
  • Intake manifold runners: The intake manifold runners can warp over time, causing vacuum leaks and performance issues. Symptoms include rough idling, stalling, and reduced power. Replacing the intake manifold runners typically costs $500 - $700+.
  • Cam position sensor failure: The cam position sensor can fail, causing the engine to run poorly or stall. Symptoms include engine misfiring, rough idling, and poor fuel economy. Replacing the cam position sensor typically costs $200 - $300+.

Transmission

• 5-speed Manual Transmission:
  • Grinding gears: The transmission may grind gears when shifting, especially in reverse. This issue can be caused by worn synchronizers or shift forks. Repair typically involves rebuilding the transmission, costing $1500 - $2000+.
• 6-speed Manual Transmission:
  • Transmission fluid leak: The transmission may leak fluid from the seals, causing low fluid levels and potential damage to the transmission. Replacing the seals and topping up the fluid is the solution, typically costing $200 - $400+.

Suspension

• Front suspension:
  • Strut mounts: The strut mounts can fail prematurely, leading to a clunking noise and reduced handling. Replacing the strut mounts typically costs $200 - $400+.
• Rear suspension:
  • Sway bar end links: The sway bar end links can become worn, causing rattling noises and reduced handling stability. Replacing the end links typically costs $100 - $200+.

Electrical

• Battery drain: Some Miatas may experience battery drain while parked. This issue can be caused by faulty alternator diodes, parasitic draws, or weak batteries. Diagnosing and fixing the cause of the battery drain can be time-consuming and costly.
• Electrical shorts: Electrical shorts can occur in various wiring harnesses, leading to various electrical issues, such as flickering lights, failed components, or battery drain. Repairing electrical shorts can be difficult and expensive.

Exterior

• Convertible top problems: The convertible top can experience issues such as tearing, leaks, or malfunctioning switches. Repairing or replacing the convertible top can be costly, typically ranging from $500 - $2000+.

Interior

• HVAC blower motor failure: The HVAC blower motor can fail, causing a lack of air flow from the vents. Replacing the blower motor typically costs $200 - $400+.
• Door lock actuators: The door lock actuators can fail, preventing the doors from locking or unlocking. Replacing the actuators typically costs $200 - $300+ per door.

Summary:

While the 1991 Mazda Miata is generally reliable, it is not immune to certain issues that can arise over time. The most common engine problems include timing belt failure and head gasket failure, which can be costly to repair. Transmission issues can range from grinding gears to fluid leaks, depending on the transmission option. Suspension problems such as worn strut mounts and sway bar end links can affect handling. Electrical issues can include battery drain and various electrical shorts. Some owners may also encounter convertible top problems or interior issues such as HVAC blower motor failure and door lock actuator failure. The severity and cost of these issues can vary significantly, so it is essential to have any potential problems diagnosed and repaired by a qualified mechanic.