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Buying Guide

Source: RX8Club.com - New and Potential Owners START HERE! Author: RIWWP

Still Ready to Buy? — Pre-purchase checklist​

So, if, after reading everything above, and you still want to purchase an RX-8, here is a list of things to look for and/or ask questions about. (RX8Club) Private sellers are more likely to know the answers, dealers less likely.

Note: These are in ADDITION to any questions that you should ask of any car you are thinking about buying, regardless of year, make, or model. These are RX-8 specific questions only.

Any item with a blue Mazda next to it can be answered by calling Mazda if the seller doesn't know (or you think they are making it up / lying).

Any item with an orange year next to it means that the question applies for that year.

Questions to Ask the Seller​

  • Engine already replaced? [Mazda]
    • Mileage of the current engine? [Mazda]
  • Engine compression
  • Catalytic converter replaced?
  • Mileage of last coil pack change
    • Have any coil packs already failed with the current cat?
  • Mileage of last spark plug change
  • Mileage of last spark plug wire change
  • Has the vehicle ever been flooded? (info about remaining cat lifespan)
  • Taillights already replaced? [2004, 2005]
    • If not, have the seals been replaced or the lights modified to drain water?
  • Oil consumption (ask how many miles between each quart or half-quart top-up)
  • MSP 13 performed by a dealer, date/mileage [Mazda 2004, 2005]
  • Typical fuel consumption
  • Odometer miles when the low fuel light comes on
  • Starter replaced with the improved version? [2004, 2005]
  • Temperature control button already replaced or repaired? [2004, 2005]
  • Clutch pedal assembly already replaced, re-welded, or reinforced?
  • Cold start time
  • Hot start time

Come back here with the answers and we can give you a heads up or a general idea on any red flags or warnings to keep in mind. Not all of them would mean "don't buy", but may help reduce the asking price.

Contact Mazda North America​

By Phone: 800-222-5500 Monday – Friday, 6:00am to 4:45pm PST

Mazda North American Operations P.O. Box 19734 Irvine, CA 92623-9734 Attn: Customer Assistance Center

I Am Buying It! What Should I Address First? — First things to address​

Generally, the more history on these items you can get from the prior owner, the better. These are all RX-8 specific. They are in addition to typical items like brakes and tires. Every item on this list is on it because it either fails regularly OR a failure of the point will result in significant cascading damage and costly repairs.

This is also the long term recommended maintenance list from us here on RX8Club.com.

At 30,000 miles and above​

  • Replace ignition coils
  • Replace spark plug wires
  • Replace spark plugs
  • Clean MAF (mass air flow sensor)
  • Clean ESS (e-shaft sensor)
  • Reset ESS profile
  • Clean power steering connections
  • Clean battery terminals and clamps
  • Replace transmission fluid
  • Replace coolant (Mazda FL-22 recommended: link)
  • Replace air filter
  • Replace brake fluid (brakes AND clutch)

~$300 USD in parts.

At 60,000 miles and above​

...everything above, plus...

  • Clean all electrical chassis ground points
  • Replace accessory belts
  • Clean OMP lines
  • Replace rear differential fluid
  • Replace thermostat
  • Clean / Straighten AC condenser fins
  • Clean / Straighten oil cooler fins
  • Inspect catalytic converter
  • Clean / Inspect intake valve
  • Consider / Inspect also the 90,000+ items

~$130 USD in parts.

At 90,000 miles and above​

...everything above, plus...

  • Replace coolant reservoir
  • Replace radiator hoses
  • Replace radiator
  • Replace front O2 sensor
  • Replace engine mounts
  • Inspect clutch pedal assembly (bending / broken welds)

~$900 USD in parts.

Note: This is not a dealer maintenance checklist filled with questionable superficiality. Every item on this list is something that typically fails in this mileage range, and for each item, if it fails, it will either leave you stranded or cause significant additional costly damage. (RX8Club, Mazda Owner's Manual)

Key System Functions and Critical Components — Critical components​

System functions and their critical components​

Starting the Engine (Starting the Engine)​

Starter, Battery, Engine Compression, Grounding Wires, Ignition Coils, Spark Plugs, Spark Plug Wires, Fuel Pump, Fuel Injectors

Generating Power at Full Throttle (Generating Power at Full Throttle)​

Ignition Coils, Spark Plugs, Spark Plug Wires, Engine Compression, E-Shaft Sensor (ESS), Air Filter, Intake Valving, Throttle Body, Mass Air Flow Sensor (MAF), Fuel Pump, Fuel Injectors, Catalytic Converter (Cat)

Keeping the Engine at a Cruise (Keeping the Engine at a Cruise)​

Ignition Coils, Spark Plugs, Spark Plug Wires, Engine Compression, E-Shaft Sensor (ESS), Intake Valving, Throttle Body, Mass Air Flow Sensor (MAF), Fuel Pump, Fuel Injectors, Front O2 sensor, Catalytic Converter (Cat)

Keeping the Engine at an Idle (Keeping the Engine at an Idle)​

Ignition Coils, Spark Plugs, Spark Plug Wires, Engine Compression, E-Shaft Sensor (ESS), Mass Air Flow Sensor (MAF), Front O2 sensor, Catalytic Converter (Cat), Intake Vacuum

Managing Engine Heat (Managing Engine Heat)​

Radiator, Thermostat, Radiator fans, Water Pump, Coolant Lines, Coolant Temp Sensor (ECT), Oil Coolers, Oil Cooler Lines

Managing Exhaust Emissions (Managing Exhaust Emissions)​

Catalytic Converter, Air Injection Pump, Front O2 sensor, Rear O2 sensor, Coolant Temp Sensor (ECT)

Changing Gears (Changing Gears)​

Clutch Pedal Assembly, Clutch Master Cylinder, Clutch Slave Cylinder, Clutch Fork, Release Bearing (Throwout Bearing), Clutch Pressure Plate, Clutch Disc, Flywheel, Pilot Bearing, Transmission Shifter, Transmission Syncros

Bringing the Car to a Stop (Bringing the Car to a Stop)​

Brake Pedal Assembly, Brake Master Cylinder, Brake Power Booster, ABS Junction Block, Brake Lines, Brake Fluid, Brake Calipers, Brake Pads, Brake Rotors

Providing Electrical Power (Providing Electrical Power)​

Battery, Alternator, Grounding Cables

Details on certain critical components​

Battery (Battery)​

The battery stores the electrical charge needed to power the starter. If a battery's charge is low, or the connections are corroded/dirty, it will not be able to deliver much power to the starter, reducing the speed of the starter or preventing it from spinning at all. Batteries need to be replaced every 3-7 years, depending on what type/quality of battery you last bought. The battery is easily reached, and replacement is very simple. Do not connect a battery backwards! You will blow fuses and possibly damage very expensive electronics.

Engine Compression (Engine Compression)​

The engine's compression of the air/fuel mixture is directly related to how effective the combustion is at pushing the rotor. Worn seals will reduce engine compression. Lower RPM will reduce engine compression. Low cranking speeds from either a dying starter or weak battery will reduce compression at starting.

Starter (Starter)​

The starter is an electric motor that accepts 12v power from the battery to power it, and a gear that engages the flywheel to spin the engine when the engine isn't running under it's own power. If the starter can't spin the engine fast enough, there will be starting problems. The faster a starter can spin the engine, the more immediate the engine fire-up will be. Starters, like any other electric motor, slow down over time and will eventually wear out. The starter is easily reached under the car, and replacement is very simple to DIY.

USA Engine Core Warranty Extension — Extended engine warranty (USA)​

Partly for public relations, partly for emissions compliance, Mazda extended the Powertrain warranty coverage on the engine core components from 5 years 60,000 miles to 8 years 100,000 miles (Mazda SSP77 warranty extension). This applies to ALL RX-8, regardless of model year.

RX-8 Rotary Engine Core Limited Warranty Extension

Mazda Motor Corporation is extending the warranty coverage on Rotary Engine Core Components on all RX-8 vehicles produced after the 2004 model year. The warranty coverage for the Rotary Engine Core Components is extended to 8 years (96 months) from the original warranty start date, with a 100,000 mileage limitation. The following is a list of components covered by this warranty:

  • Rotary Engine Core
  • Rotary Housing and Internal Parts
  • Internal Seals and Gaskets

THIS IS NOT A RECALL! (Mazda SSP77) People often mistakenly refer to the warranty extension as a recall, but it is not.

This is an extension of an existing warranty. It works like any other warranty. Owners need to meet the same requirements for this warranty as any other warranty. I.E Maintenance records, proof of a problem, etc...

The expiration date depends on when the car was first sold. If your car sat on the original dealer's lot for a year, it postpones the start of the warranty by the same amount. My 2005 wasn't sold until September of 2006, so my 8 year mark was pushed back to September of 2014. There are a few rare cases where the car's warranty period started before the car was sold, such as if the dealer registered it for use as a dealer vehicle.

Obtaining Warranty Coverage — Obtaining warranty coverage​

In simple terms, a warranty is when a company legally accepts financial liability for a failure for a specified time period. This doesn't have to be the manufacturer, though it usually is.

When something breaks on your car, and it should be covered under warranty, your request for warranty service is legally a request for the warranty issuer to accept liability for damage/repairs as agreed.

If the warranty issuer accepts liability, which is usual, then they reimburse the shop for the costs of repairs. This is true even of dealers. Dealers charge the cost of repairs to Mazda USA, and get reimbursed. They make a lot of money on engine replacements. This is a critical point to keep in mind. The dealers can choose to not even file for warranty coverage (usually due to laziness), or they intentionally or accidentally misrepresent your car and modifications to Mazda USA during the discussion when Mazda is deciding on if they will accept the liability or not.

If a warranty issuer decides they don't want to accept liability, then there is a fight ahead, at some level. Dealers are notorious for making this decision without even asking their parent company. However, another critical point to recognize is that when a vehicle that is still within warranty period is denied warranty coverage, the warranty issuer has the burden of proof legally. They have to prove that a non-OEM part, a non-approved action, or a lack of required action caused the failure.

Maintenance records is the big one. For all of history of warranties being issued, dealers have asked for maintenance records as proof of service before coverage. However, it isn't actually proof. Records simply close a loophole that they might try to exploit to get out of accepting liability. A vehicle with no service records at all can have an engine failure, and the warranty issuer has to prove that a lack of service caused the failure. Legally. Of course getting to that point might still be costly fighting that battle, whether in time, money, and/or stress.

Given the history of failure with this engine, if it got to a legal fight, Mazda has very little chance at winning unless there was something changed about the engine itself (turbo, supercharger, oil, seals, rebuilt, etc...).

Two realistic options​

  1. Build a relationship with your local dealer, absorbing the additional cost in time and money for routine maintenance to develop that relationship and set the stage in case of a warranty claim.

  2. Do everything yourself, and any warranty claim is more occasional, where you are prepared to bear the costs if the claim is denied.