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hey I have 2 questions

went to a khanacross on the weekend but sadly my car broke before I arrived.

I thought it was fuel pump but that works fine. I have also replaced the circuit opening relay(fuel pump relay) because I was only getting 6v at the fuel pump when the key was in "on" position.

now I am home (car is 100km away) I have studied the wiring diagrams and think theres only a few possibilities.

the main possibility seems to be the main relay which would explain why the injectors werent clicking. but from what I have read is if the injection main relay is gone you dont get spark either as it sends a signal to the cas. I was getting spark as heard by clicking.

so is it still possibly the main relay considering I do get spark? I do have a cops conversion if that makes a difference.

if so what relay can I replace the main relay with (mazda wanted $145)

thanks for your time

2 options:
1. Pry the cover off the top of the relay and see if the points are pitted or out of alignment. You can clean the points like you used to on an old dizzy, bend them to adjust gap and straighten them. That can give the relay another few months of life while you find a cheaper new one.
2. Mazda 323s and Astinas of around the same vintage used the same relay. Check the wreckers. $10?

Just realised your car is 100km away so you can't easily look at the relay. It looks like the B6S8 in any of these pics.
http://www.ebay.com/sch/i.html?_trksid= ... y&_sacat=0

Mazda just quoted me $250 for a pump relay for a na6.. Anyone wireup something non standard? I was thinking of a high current solid state unit to prevent maintence and would possibly give a cleaner power source.

Thoughts?

It'll probably cost you less than $10 from someone like RS Components and you'll get a far better component. You just need to use good quality wire and terminals and do your reading on relay pin-outs.

I once did a pin-out diagram for the MAIN relay. I think they're all the same pattern. I'll have a hunt for it later.

Edit: Got it. Hope it helps. I won't be responsible if you burn your car to the ground though.

manga_blue wrote:Edit: Got it. Hope it helps. I won't be responsible if you burn your car to the ground though.

thankyou for sharing the info - the mx5 community are a friendly and helpful bunch.

With your help and some experimenting I think ive got a working relay.
To hopefully help others this is what ive found.

When replacing denso part 056700-6381 12v
excuse the text drawing:

Looking at the plug on the car: (the [!] is the lock pin.)

..........[!]..............
[pin1] [pin2] [pin3]
[pin4] [pin5] [pin6]



The na6 fuel pump relay has 5 active pins -

pin 1 - output to the pump. Should = +12 when engine is running.
pin 2 - 12v from fuse/battery
pin 3 - Goes to ground when air flow meter is moving ( purple wire)
pin 4 - goes to ground when starter motor is engaged (green wire)
pin 5 - empty
pin 6 - ground

The standard relay uses separate triggers for the pump
trigger 1 [pin4] is from the starter motor(goes negative)
trigger 2 [pin3] is from the airflow meter(goes negative)

What ive done is buy a standard 4 pin relay with plug and flyleads and a diode. about $11 in total

standard +12 'horn' relay pinout to mx5 / miata
on the relay:
86 - join to 30
30 - (joined to 86) to +12 = pin 2
87 - pin 1
85 - branch to 2 wires. wire 1 use diode with its banded end on relay joined to pin4
wire 2 goes to pin3

With this setup the starter motor triggers the relay and the airflow meter continues this after starting.
The diode stops the airflow meter triggering the starter motor after starting(this is bad and the diode is important).

The car seems to run nicely with this - I'll test tomorrow with a long drive and report back.

btw manga_blue - i will use your diagram to replace the ecu relay also. Its 26 years old and putting a $7 new relay there does seem like a good idea.
cheers

Check to see if MX5 Mania would have one.
A few weeks ago i needed a new Fuel Pump Relay, got quoted $165 from one of the main Mazda parts suppliers in Newcastle.
Rang Mania and drove down to pick one up for $36. WIN!