Use and Interrogation of the Diagnostic Connector
 

Does anyone know where I can find a guide ONLINE for this.

supposodly it:

This manual explains the functions and uses of that mysterious black box located near the air filter-the diagnostic connector. The procedures apply equally to most models of Mazda MX5, Miata, and Eunos Roadster 1989>1998. The purpose of this manual is to enable the home mechanic or independent garage to access the self diagnostic facilities of the MX5 which are normally only available to Mazda dealers through the use of their factory provided service tools. Includes a free DIY led probe to get you started!

cheers

miata.net garage

do you have alink as a shop in the uk is charging ££££ for a guide and a wire with an LED oon it.

cheers

anyone.?????

I really think my rich running is down to the thermosensor at the back of the engine under the coilpack....:confused:

go get a led from whatever electronic parts store you guys have over there, then look at the guide in the m.net garage.

sorry but is that what i am supposed to be looking for:

http://www.obdii.com/codes.html

cus that to me is just some random figures.

it does not tell me the procedure.:confused: :confused:

no tabs that isnt for your car mate. Ill have a look for the Mk1 codes.


here you go.

http://autorepair.about.com/library/...l-dtcs-25a.htm

nice one. your a star.

what do I do with the 12v Led now??:confused:

thanks.

Now where does the 12v led come into it?

don't need it for us spec cars.

you'll need a 470-600 ohm resistor to make the led work properly w/o burning it out...

Except that shows a code for an EGR which a 1992 does not have. I'd use the m.net chart instead.

FWIW, I removed the diagnostic connector from my '91. You would not believe how much wire is used for that thing (probably not an issue for most of you but I bet it was over 100 feet!).

Here is a pic I found of the AFM wiring (gives you an idea of what is on the diagnostic connector:

http://ww2.lightweightmiata.com:8080...e/rewire11.JPG

thanks guys!

:vash: :vash: UPDATE:

Finally did this today and it threw code: 17.

I am getting Just over 250km from a tank of petrol on mostly stop/start journeys.

O2 Sensor!!!:vash: :vash:

This is my second 4-wire bosch sensor this year.

I believe the problem lies somewhere else now why it keeps killing the o2 sensor..!!

Any ideas what could be causing the problem?


Water thermosensor?

bad wiring?

Injectors leaking?

Fuel filter clogged?
The use of the Vortech FPR with Emaanage and 1.8 injectors surely cant be causing an excessively rich mixture can it?

The car is also missing...but there is another thread on this!!:confused:

Any helpful replies are welcome

From what I am told, overly rich conditions will kill an O2 sensor. However, just because you throw an O2 code that doesn't mean the sensor is dead. I regularly get a check engine light on my wife's "very rich for a few more days" Miata. As soon as I let off the gas the light goes away and I don't believe the sensor is actually dead.

You can throw an o2 code if the sensor is good if the car constantly runs rich. The ecu is looking for rich/lean/rich/lean, if it stays rich (due to a problem with a different sensor) for a set time, it will also throw an o2 code.

my suspicians point to a bad water thermosensor at back of engibe under coil pack.


Or a sticking AIR FLOW METER.

Both are directly involved wit air/fuel.

Gonna order new thermosensor and get hold of a second hand AFM once Xmas is over nd will report back.

Is your bumper black? Are you plugs white?