Replacing The Fuel Pressure Regulator In A 1999 Miata

If you're looking to replace the fuel pressure regulator on a 1999 Mazda Miata, there are a few things you should know. Firstly, the regulator is located on the fuel rail, and there are videos available online that demonstrate the replacement process. While it is possible to replace the regulator yourself, it is important to note that there are different types of fuel delivery systems, and Miata's fuel delivery system has been known to contribute to reliability issues. Contamination in the fuel tank can be a problem, as the fuel pump can pick it up and push it through the regulator, leading to potential issues such as misfires, coil pack failures, and injector failures. To address this, some people choose to retrofit the return system or use aftermarket components to allow adjustability of fuel pressure. It is also recommended to change the fuel filter regularly and drain the fuel tank to improve the system's performance. When replacing the fuel pressure regulator, it is important to ensure that all the necessary parts are compatible and properly connected to avoid any issues.

The regulator is located on the fuel rail

The regulator can be replaced by purchasing a Mazda Miata Adjustable Fuel Pressure Regulator kit, which is designed for 1999-2005 Mazda Miatas. This kit utilises high-quality AN fittings with braided lines and can be installed without any cutting. It is designed to be mounted in the trunk of your 1999 Miata.

There are also videos on YouTube that show people replacing the FPR on Miatas, which may be helpful for further instruction and a more visual guide.

There are videos on YouTube showing the replacement process

One video, in particular, provides a step-by-step guide on how to replace the fuel pressure regulator on a 1999 Miata. The video covers the tools and parts required for the job, as well as offering detailed instructions on how to access and replace the regulator. It is a comprehensive and instructive video, offering a clear and concise process for viewers to follow.

The video also highlights some of the common issues that may be encountered during the replacement process, such as different mounting and hose connections on the replacement part. It offers solutions and workarounds for these potential problems, ensuring that viewers are well-equipped to tackle the task.

Additionally, the video provides valuable insights into the function and importance of the fuel pressure regulator, helping viewers understand the role it plays in the fuel delivery system. This includes an explanation of how contamination can build up in the fuel tank and the steps that can be taken to mitigate this issue.

By following the step-by-step guide and tips provided in this video, viewers can confidently and effectively replace the fuel pressure regulator on their 1999 Miata, ensuring optimal fuel pressure and engine performance.

The regulator is in the trunk of the 99-05 Miata

The regulator is located in the trunk of the 99-05 Miata. It is designed to be easy to adjust and doesn't require any cutting to be installed. The regulator uses a Fuelab regulator and features a fuel sample port on the front.

To access the regulator, open the trunk of your Miata. It is mounted in the trunk and can be reached without having to cut or modify any parts of the car. This makes it a convenient location for adjustments or replacements.

The fuel pressure regulator in the 99-05 Miata is an important component of the fuel delivery system. It is designed to regulate the fuel pressure and ensure optimal performance. By mounting it in the trunk, it becomes easily accessible for adjustments or replacements if needed.

It's worth noting that some people choose to install an aftermarket fuel pressure regulator in a different location, such as under the hood close to the fuel rail. However, the stock location for the 99-05 Miata is indeed in the trunk.

If you are considering adjusting or replacing the fuel pressure regulator in your 99-05 Miata, it is always recommended to refer to the service manual or seek professional assistance to ensure the work is done correctly and safely.

The regulator is easy to adjust

The 5X Racing 1990-1997 Mazda Miata Adjustable Fuel Pressure Regulator is another option that is easy to adjust. It uses the factory vacuum line, which keeps the pressure consistent. This product allows you to adjust your fuel pressure at your fuel rail by simply turning an adjustment screw.

There are other options available for adjustable fuel pressure regulators for the Miata, which may also be easy to adjust. One option is to retrofit the return system as the 1997 and older Miatas had, or use aftermarket components to allow adjustability of fuel pressure. This can be done by mounting an adjustable fuel pressure regulator under the hood, in the return line close to or on the fuel rail, with the return line back to the tank.

Another user has suggested that the stock vacuum line location should be retained, with the side going to the adapter plate/fuel rail, the other side going to a gauge, and the bottom going back to the tank (the hardline).

The regulator may have been modified to cheat in races

One way to cheat in races is by manipulating the fuel flow sensor. In the case of the 2019 Scuderia Ferrari, their cars' performance dropped off after a "technical clarification" from the FIA, leading to speculation that they were interfering with the fuel flow sensor. This theory was supported by the discovery that one of their cars was carrying too much fuel at the Abu Dhabi Grand Prix, which could explain their power advantage.

Another way to cheat is by altering the intercooler, allowing oil to escape into the combustion chamber. This oil would be burned during combustion, resulting in a more powerful "bang" and improved piston performance.

While there are no specific examples of cheating with a 1999 Miata fuel pressure regulator, the universal nature of fuel pressure regulators means that similar modifications could be made to gain a competitive edge. However, it is important to note that cheating in races is unethical and can lead to disqualification and other penalties.

Frequently asked questions