Q&A

If the second BOX is powered on, you can connect it by going to "Settings" in the TDI Tuning app, then "Delete System" → "Add System" → "Enter Pairing Number."

Subsequent connections after the first time will not require entering the pairing number.

A. This product is compatible with most diesel engines and gasoline turbo engines manufactured after 2000, as well as some vehicles manufactured before that. If you would like to confirm compatibility for a vehicle not listed, please feel free to contact us at info@m-flow-tdi.com.

A. It can be installed on a wide range of vehicles, from those that have just been delivered new to those with over 200,000 miles. For new cars, we usually recommend installing it after a break-in period of a few hundred miles. For vehicles with high mileage, it will perform well if properly maintained, but there is a tendency for some performance to be lost compared to when the car was new, so it may be difficult to achieve exactly the same performance figures as a new car.

All TDI Tuning devices are safe and will not damage the engine in any way. TDI Tuning has been tuning diesel vehicles for many years and has extensive knowledge and experience of what settings are required for each device installed in a particular vehicle. The products do not alter the information held in the ECU, and the manufacturer's safety settings remain intact, ensuring that the set values do not exceed safety standards. You can rest assured that the engine is fully controlled by the vehicle's own safety features and will not override or modify any of the vehicle's settings.

A. While Single Channel controls only fuel delivery, which is effective, Twin Channel controls both fuel delivery and boost. This typically results in an approximately 5PS power increase and 0.2L/100Km fuel efficiency improvement compared to Single Channel, along with smoother operation.

A. All of our tuning boxes come with a 14-day money-back guarantee and a 5-year product warranty.
However, costs not related to the product itself or its data program, such as expenses for clearing check engine lights, towing fees, and shipping costs for product inspections, will be borne by the customer.
Furthermore, the warranty becomes void if the product is transferred or resold.

*When applying the 14-day money-back guarantee system

・Please send the product with all labels, accessories, etc., in their original condition, free from dirt, dents, or scratches (in resalable condition).
・Shipping costs will be borne by the customer.
・A separate administrative fee of 2,000 JPY will be charged.

A. In principle, there should be no particular problem. If you are concerned, you can return it to its normal state without removing the entire harness by installing an optional removable cap instead of the BOX unit.

A. We can only assist with products sold through official Japanese channels, as per our agreement with UK-based TDI Ltd.

A. Most tuning boxes connect to the fuel injectors in the engine bay. The harness has genuine male and female connectors, so by removing the connector from the vehicle's engine, plugging it into one of our harness connectors, and returning the other connector to the vehicle's engine, the tuning box will function in line with the vehicle's electronics. Since it's just a matter of plugging into the engine, installation only requires basic tools like a screwdriver. Please refer to the installation manual for details. A Japanese version is also available.

A. After purchasing from our website, you should be able to have them installed at a local car or tire shop. We recommend consulting with a shop near you.

A. No, the device is designed to maximize efficiency and will not negatively impact exhaust emissions.

A. This depends on the policies of each car dealer, so we recommend checking with them. If you are concerned, you can return to the normal state without removing the entire harness by attaching the separately sold removable cap in place of the BOX unit.

A. Car manufacturers do not develop vehicles according to the climate and conditions in which they will be used. Instead, they develop vehicles that can be used worldwide, even under conditions with different fuel qualities. Also, to reduce production costs, they use the same engine to provide various different power outputs, or they take an excessive safety margin for the engine to place the vehicle in a lower tax bracket. By slightly reducing that margin, we provide data programs that prioritize safety, reliability, and durability without compromising engine longevity. Furthermore, TDI Tuning implements continuous inspection and development programs for all its products, with extensive testing by the technical team and test drivers before product launch. By conducting both road tests and dyno tests at independent tuning centers, the technical team sets safe levels while significantly improving performance and fuel efficiency.

A. It can be installed on gasoline turbo vehicles. If it is not listed in the product lineup, please contact info@m-flow-tdi.com.

A.Yes, it is possible if the vehicle is compatible. In that case, please send the BOX to us, and after reprogramming, we will send it back to you along with the harness compatible with the new vehicle. Please see here for pricing: https://m-flow-tdi.com/collections/reprogramming

A. TDI Tuning is programmed to maximize efficiency and maintain an appropriate balance in the air-fuel mixture, so it does not increase exhaust emissions.

A. TDI Tuning only affects the actual parameters of the ECU that need to be changed, so there is no interference with other electronic devices.

Although TDI Tuning is water-resistant, it is not completely waterproof. If it were fully submerged, water could enter the box, but this rarely happens as it is designed for use within the engine bay.

A. The maximum temperature is 268°C. The device is designed to withstand temperatures within the engine bay, but please avoid installing it near extremely hot engine components such as the turbo or exhaust system.

A. TDI Tuning optimizes fuel pressure and quantity to improve performance. For example, it continuously optimizes fuel injection quantity according to driving conditions, such as increasing it at low RPMs and decreasing it once a certain RPM range is reached. Car manufacturers often detune engine performance to ensure consistent operation across a wide range of fuel qualities and extreme environments worldwide. The CRTD4 unlocks this restricted performance. The Twin Channel, by controlling boost in addition to fuel, allows for smoother power and torque delivery from low to high RPMs and also reduces turbo lag.

A. For boost gauges that connect to the OBD port or factory-installed boost gauges that use a CAN connection, the boost pressure will be displayed lower after installation than it was when stock. This is because the TDI Tuning main program is designed to increase boost pressure by changing the boost sensor signal to a lower value than stock. In this case, accurate readings can be obtained by using a boost gauge connected directly to the intake manifold.

A. In principle, the check engine light should not illuminate and error codes should not appear. However, depending on individual vehicle differences, modifications, or installation issues, the check engine light may illuminate. In such cases, please provide information such as the error code content, conditions when the check engine light illuminates, and BOX settings, and we will respond accordingly. This will be covered free of charge during the 5-year warranty period. However, in some cases, a boost pressure increase may reveal issues such as a faulty sensor or worn spark plugs; in these situations, please replace the sensor or spark plugs.

A. TDI Tuning can be set to accommodate light tunes such as ignition system, muffler, and OEM replacement air cleaner modifications. However, depending on the type of muffler, the boost pressure may increase, causing the check lamp to illuminate. In such cases, if it is within the warranty period, we will reprogram it to suit the situation.

A. This could lead to excessive power output and potentially damage the engine, so it should be strictly avoided.

I hope this information is helpful.

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