There was a thread on this.
The NA Miata ran on gasohol, which is 10% ethanol pretty much from year zip. From the 1994 Miata owners handbook:
So 10% ethanol would not void the warranty. That’s a strong endorsement.
I asked questions of Mazda UK, and either they are idiots, or they simply don’t care about obsolete models (Mazda UK; if you are reading, please feel free to chime in, you have done rather will off the MX5 community over the years).
The responses indicated they really didn’t have a clue, and certainly were still spouting the same prejudice about imports as 20 years ago (they need to get over themselves).
Thank you for your email. I have checked with our Technical Support Team who have confirmed the information we have from Mazda Corporation states that for vehicles sold in Europe, only vehicles first produced (Not registered) after 2002 are compatible for use with E10 fuels.
I can confirm that vehicles sold in the US markets are subject to very different emissions laws and therefore differ in specification. Unfortunately, we do not have details of these differences as we only have access to the information relating to vehicles produced for sale in Europe.
And
We think the misunderstanding here is because the broader statement simply quotes the 2002 date, which relates to new model types introduced from this date – not individual vehicles registered from this date. For individual vehicle lines, the factory supplied us with the information shown on the DfT’s E10 compatibility tool which is also shown on the Mazda UK website.
To re-iterate, the information shown on the Mazda UK Website and within the Government’s E10 compatibility tool is correct for all vehicles that were originally built to UK specification. Unfortunately we are unable to confirm whether your understanding of the similarities between the Miata and the MX-5 are correct as we do not have this information. For non-UK models we would recommend that reference is made to the owner literature supplied with the vehicle to determine the correct fuel type.
In other words, Mazda UK, Mazda Japan, really cannot be bothered to:
- Identify which parts might be of concern
- Cross reference US, EU, Japan part numbers. 30 years ago, this might have been a valid excuse when they claimed all the parts were on Microfiche, and the JDM lists were in Japanese only (this is literally what they told me back in 1997, when I asked if a Momo horn button for for 1992 UK car would fit a 1992 Eunos Roadster).
I did a partial mapping using readily available online sources, but must have gotten bored of it. Mazda really ought to be doing this; if they really really think US cars had a fuel system that is significantly dfferent from other markets, and give the global supply of car parts now, they really have a Duty of Care to provide a rather better response than the half hearted response that raises the risk of NA cars catching fire. But really, they don’t care about NA owners, unless they are buying a new ND.
We all know the US is highly litiguous. The warranty statement is very strong. For them to have said that in 1994 indicates (1) they knew which parts were at risk (in contact with fuel) (2) they had carried out a materials analysis, which would have involved checking with suppliers. I am surprised Mazda UK is ignorant of this.
In the US, there are grades of fuel with very high ethanol content (E85); NAs might run a bit rough on this, but I have seen zero evidence of vehicle fires caused by ehtanol content in Miatas.
The revenue Mazda UK derives from NA parts sales must be by now insignificant, so I am not sure why they are evasive.
Some samples (EUDM; EU/EU spec. JDM; Japan spec, USDM; US spec. Used a 1996 vehicle as a reference) from my homemade comparison.
| Column 1 | Column 2 | Column 3 | Column 4 |
|---|---|---|---|
| **Market | Product Name | Part Number | |
| JDM | Filler pipe gasket | 0866-42-366B | |
| USDM | Filler Pipe Gasket | 0866-42-366B | |
| EUDM | GASKET,FILLER PIPE | 0866-42-366B | |
| JDM | Grommet | 8574-13-252 | |
| USDM | Fuel Injector Seal, Upper | 8574-13-252 | |
| EUDM | GROMMET | 8574-13-252 | |
| JDM | O-ring | 8574-13-253 | |
| USDM | Fuel Injector O-Ring | 8574-13-253 | |
| EUDM | RING,‘O’ | 8574-13-253 | |
| JDM | Evaporation hose | B61P-13-973A | |
| EUDM | HOSE,EVAPORATION | B61P-13-973A | |
| JDM | Drain hose | B61P-13-97YA | |
| JDM | Fuel pump filter | B61P-13-ZE1 | |
| USDM | Fuel Filter | B61P-13-ZE1 | |
| EUDM | FILTER,FUEL PUMP | B61P-13-ZE1 | |
| JDM | Fuel Distor Insulator | B675-13-158 | |
| USDM | Insulator Fuel | B675-13-158 | |
| EUDM | INSULATOR,FUEL DIST. | B675-13-158 | |
| JDM | Ventilation hose | B6CA-13-971 | |
| USDM | Hose Vent | B6CA-13-971 | |
| EUDM | HOSE,VENTILATION | B6CA-13-971 | |
| JDM | Evaporation hose | B6CA-13-972 | |
| USDM | Hose Evaporative | B6CA-13-972 | |
| EUDM | HOSE,EVAPORATION | B6CA-13-972 | |
| JDM | Fuel vapor valve | BC1M-42-980A | |
| USDM | Vapor valve | BC1M-42-980A | |
| EUDM | VALVE,FUEL VAPOR. | BC1M-42-980A | |
| JDM | Fuel injector | BP06-13-250 | |
| USDM | Remanufactured Fuel Injector | BP06-13-250 | |
| EUDM | INJECTOR,FUEL | BP06-13-250 | |
| JDM | Fuel distributor | BPE8-13-150 | |
| USDM | Fuel Rail | BPE8-13-150 | |
| EUDM | DISTRIBUTOR,FUEL | BPE8-13-150 | |
| JDM | Sub fuel pump | BPE8-13-350 | |
| USDM | Electric Fuel Pump | BPE8-13-350 | |
| EUDM | PUMP,FUEL-SUB | BPE8-13-350 | |
| JDM | Fuel pump | BPE8-13-35Z | |
| USDM | Fuel Pump Assembly | BPE8-13-35Z | |
| EUDM | PUMP,FUEL | BPE8-13-35Z | |
| JDM | Fuel hose | BPE8-13-495 | |
| USDM | Hose fuel | BPE8-13-495 | |
| EUDM | HOSE,FUEL | BPE8-13-495 | |
| JDM | Fuel hose | BPE8-13-49X | |
| USDM | Hose Fuel EGI | BPE8-13-49X | |
| EUDM | HOSE,FUEL | BPE8-13-49X | |
| JDM | O-ring | G601-13-253 | |
| USDM | Fuel Injection Pressure Regulator O-Ring | G601-13-253 | |
| EUDM | RING,‘O’ | G601-13-253 | |
| JDM | Check valve | GA5R-42-910 | |
| USDM | Check vlv | GA5R-42-910 | |
| EUDM | VALVE,CHECK | GA5R-42-910 | |
| JDM | Non-return valve | H260-42-270 | |
| USDM | Check Valve | H260-42-270 | |
| EUDM | VALVE,NON RETURN | H260-42-270 | |
| JDM | gasket | J004-60-962 | |
| USDM | Gasket | J004-60-962 | |
| EUDM | GASKET | J004-60-962 | |
| JDM | Injection insulator | JE06-13-257 | |
| USDM | Fuel Injector Seal | JE06-13-257 | |
| EUDM | INSULATOR,INJECTION | JE06-13-257 | |
| JDM | connector | JE16-13-298 | |
| USDM | Connector | JE16-13-298 | |
| EUDM | CONNECTOR | JE16-13-298 | |
| JDM | Canister | JE16-13-970A | |
| USDM | Vapor Canister | JE16-13-970A | |
| EUDM | CANISTER | JE16-13-970A | |
| JDM | Three-way valve | JE16-18-741 | |
| USDM | Valve | JE16-18-741 | |
| EUDM | VALVE,THREE WAY | JE16-18-741 | |
| JDM | Pressure regulator | KJ01-13-280 | |
| USDM | Fuel Pressure Regulator | KJ01-13-280 | |
| EUDM | PRESSURE RG.,FUEL | KJ01-13-280 | |
| JDM | In-tank fuel pump hose | KL19-13-ZE6 | |
| USDM | Hose Fuel Pump In Tank | KL19-13-ZE6 | |
| EUDM | HOSE,FUEL PUMP-IN TANK | KL19-13-ZE6 | |
| JDM | Filler hose | NA01-42-241C | |
| USDM | Filler Hose | NA01-42-241C | |
| EUDM | HOSE,FILLER | NA01-42-241C | |
| JDM | Fuel tank pad | NA01-42-762 | |
| USDM | Fuel Tank Pad | NA01-42-762 | |
| EUDM | PAD,FUEL TANK | NA01-42-762 | |
| JDM | Fuel tank gauge | NA75-60-960A | |
| USDM | Fuel Gauge Sending Unit | NA75-60-960A | |
| EUDM | GAUGE,FUEL TANK | NA75-60-960A |