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1,231 Posts
Discussion Starter · #1 · (Edited)
Common Faults and Rectifications -

This FAQ is designed to answer most commonly asked questions by members on this board. This is aimed at an Australian audience, so that we can have specific answers relating to our problems, and ways to rectify them. It is designed to be a technical FAQ, rather than just general questions about our cars.

Please note there is also a General FAQ on this website that can be found here.
General FAQ

1.)Throttle Body Boot Cracking, or Air Leak Post Turbo -

Problem: The throttle body boot on our cars is prone to cracking due to age and stress. This is the rubber boot around 3inches in diameter that connects your intercooler piping to your intake plenum.

The same symptoms can also be experience if you have any form of air leak post turbo going to your intake manifold. Common problems include loose intercooler pipes or hoses, leaking blow of valve, or a split in your intercooler end tanks.

Causes: If this cracks, or even has a hairline split in it (most common), air will leak out under acceleration causing the car to hesitate, idle rough, blow black smoke, stall, and also hit boost cut intermittently.

Fixes: Thoroughly examine your intercooler piping all the way from the turbo -> throttle body. You can take off the throttle body boot to examine for hairline cracks, or deteriated rubber. Also examine intercooler for cracks. A good way is to check for air leaks with the engine running.

Throttle body boots can be bought new from Mazda for around $100. Try ring around wreckers which should source them for between $20-50, but ensure it is in excellent condition.Intercooler cracks can be welded.

2.) Heater Core -

Problems: The heater core in our cars are prone to leaking. This is usually due to the end tank separating from the core over time.

Causes: Normally a big pool of coolant on your passenger side footwell. Can also cause a coolant smell inside the car, and if you loose lots of coolant, can cause the car to overheat.

Fixes: You need to replace or repair the heater core. The heater core is located under the dashboard, pretty much behind and below the glovebox compartment. The entire dashboard needs to be removed to get the heater core out, which can create a big job. Once out, choices are to buy new from Mazda (around $900) or to have a custom brass unit made (around $150-300.) This is the better option as its not only cheaper, but usually higher quality than the Mazda original. Take your old heater core to any good radiator shop, and they should fabricate one no problems for you. If you are stuck in an emergency, and cannot replace the heater core, you can re-route the heater hoses to not go to the heater core at all, and to join to each other. This is done in the engine bay, where the heater hoses connect to the core on the firewall.

3.) Exhaust manifold leak (contributed by Tripharn :tup: )

Problems: Exhaust manifolds eventually wear out, due to the constant pressure of the gas exchange from the engine to the exhaust manifold. Also, sometimes the studs snap from the twisting action of the turbo / engine.

Causes: A ticking noise from the engine, increases with revs. Sometimes goes away when the car warms up. Is quieter when at idle. Is louder when under boost. Sometimes leaves black carbon where the leak is.


1. Remove the radiator (not compulsary, but makes it easier). Remove all hoses. Undo the plastic retainers and remove radiator.
2. Remove air intake and outlet of the turbo and move it out the way.
3. Remove head shields from the manifold, two bolts on the top, a couple in the front.
4. Start disconnecting parts of the manifold and turbo...
- Unclip the O2 sensor
- Turbo oil line
5. Unbolt the turbo from the dump pipe (at least 3 bolts)
6. Unbolt the support bracket just between the turbo and the engine.
7. Unbolt the manifold from the head. There is 6 bolts, 2 on top and 4 underneath.
8. Pull out the turbo, manifold etc in one go. (Its heavy!)
9. Pull off the gasket.
10. If you have a broken stud, then either pull it out with pliers or helicoil it out, and replace it.
11. Clean the area and assemble in reverse.


4.) Blown head gasket - What to do?

5.) How to Read error codes from the ECU

6.) Diff/Gearbox Problems

1,231 Posts
Discussion Starter · #2 · (Edited)
Modifications and Upgrades

This section is to deal with common or recommended upgrades or modifications we all make to our cars. Feel free to post any questions or experiences that you've had with your own modifications.

For the purpose of this I am focusing on the turbo engined MX6/626/TX5. This is the F2T engine as delivered with our cars. If anyone would like to add information about the FE DOHC, I will include this aswell.

Common First Mods -

Want to improve your car, and just bought it, or just starting out researching your options now?

Most turbo owners will start with the following basic mods, these will be explained in greater detail further down.

Performance - Exhaust, Intake, Boost control.
Suspension - Swaybars, Good wheel alignment, Uprated shocks, Uprated springs












1,231 Posts
Discussion Starter · #3 · (Edited)


General FAQ

This is designed to be a General FAQ about our cars. The aim is to help new members (or old ones) learn more about their cars details.

Any questions you feel should be in here, or would like answered, please PM me, or just ask them here and I will edit them in. Thanks!


Q What cars are referred to as a 1st Gen?

A All 1987-1991 Model MX6/626/TX5'S are generally referred to as 1st Generation cars. Although this is technically only accurate for the MX6, these models share the same configuration, so generally get referred to the same.

Q What parts are common between MX6/626/TX5?

A All the above cars are based on the same floorpan. The drivetrain configuration, and motor are the same, aswell as the majority of chassis components. It's best to check with parts dealers if a particular part is shared, or ask our friendly members.

Q What is the factory performance of these cars?

A The turbo models put out 108kw of power and 233nm of torque when run on premium unleaded petrol. They loose a little when run on standard unleaded. As an approximation, this equates to around 85-90 kw ATW on a reliable dyno.

Performance figures can vary wildly due to conditions, and condition of your car. But as an approximation, 0-100's in around 8.5 seconds stock, and 1/4 mile in around 15.5-16.0 should be expected.

Q What is the performance potential of these cars?

A This can be a controversial topic, but please remember this is intended as a guide only.

Mild Modifications - Modifications such as an upgraded exhaust, intake, and around 12psi boost should see your 1st gen able to produce mid to high 14 second performance. Power output approximately 110kw-120kw ATW. Further mods such as a high flow turbo, and retuned ECU to allow approx 15-16psi should see around 130-140kw ATW, and low 14 second, to high 13 second performance.

Heavy Modifications - More modifications to your 1st Gen would include the path of upgraded turbo, upgraded intercooler, and upgraded engine management/fueling. This would require larger injectors, upgraded fuel pump, and either an aftermarket ECU or re-tuned factory ECU. Power outputs depend greatly upon the choice of turbo and the amount of boost used. A turbo such as a Garrett T28 or T03, or IHI VF22 or VF30 on around 12-15psi should see around 160-170kw ATW. More boost can see around 180-200kw ATW. Larger turbo's again can be used to achieve around 220-240kw ATW which is starting to reach the limits of the F2T's engine potential. This sort of power output would require an engine built to handle higher boost levels and a good engine tune.

Q What upgraded turbo can I use that bolts on/ How do I upgrade my turbo?

A As far as bolt on turbo upgrades are concerned (ie Turbo that will bolt up to the standard exhaust manifold, and exhaust flanges) there are none available for our cars.

Choice for upgrading or improving your turbo are as follows:

HIGH FLOW - A high flow of the standard turbo can provide slightly more airflow than the standard turbo. Common highflows modify the compressor side of the turbocharger to allow it to pump out more air. A typical highflow of this nature will cost around $700-900 including a turbo rebuild. Good for people wanting to run around 15psi, and make a small gain over standard turbo. Good for approximately 130-140kw ATW. You can also choose to modify the exhaust turbine side of your turbo when highflowing, this can make a bigger difference to the amount of air your turbo can flow, especially to the top end power. A typical highflow of this nature costs around $1200-1400. You could expect a further 10-15kw's over the cheaper highflow, but the efficiency of this turbo choice is questionable.

REPLACE TURBO - To fit a larger turbo to your 1st Gen, you have two choice. You can use an adapter plate, which is basically a flange that connects your new turbo's bolt pattern to the standard exhaust manifold. The advantage of this is low cost, and relatively simple to manufacture. Cost is generally $150-200. Your other choice is to get a custom exhaust manifold made up to suit your choice of turbo. This is more costly, normally around $600-900, but there are benefits. Your manifold can be made to position your turbo anywhere you like, and a good designed manifold should flow better than the standard manifold.

Turbo choice is up to you! As a guide decide what kind of power curve you would like/can live with. Also decide what kind of power output you would like to achieve. Good results can be had with readily available T28 turbos, found on the Nissan 200sx, the best of this bunch is the S15 T28, with more power potential, and also ball bearing core. These can be found for between $600-900. Power potential for the S15 T28 is around 170-190kw ATW on around 16-18psi. Another good choice of turbo is the IHI ball bearing VF22.These can be found for between $800-1000. Power potential also around 170-190kw ATW on 16-18psi. Other turbos to investigate are the IHI VF30, IHI VF34, or Mitsubishi TD05.

Q How do I reset the ECU on my 1st Gen?


1. Disconnect negative battery terminal
2. Press on the brake pedal for about 30 seconds
3. Reconnect battery
4. Start the car but don't touch the gas pedal for one minute!

It is a good idea to reset the ECU/computer whenever an engine, fuel, or air intake modification has been done.


please tell me how to get out the codes of a gen 1 mx6 and also pls tell me if tx6 & mx6 ecu's are swapable ta sham.

145 Posts
need infor on ecu remapping

want to get my ecu remapped for my 1st gen mx6 2.2L 12 valve. need info on this and looking to get it dun asap. just running a stocky wid pod and half cut want POWER
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