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So, last Friday the fuel pump and the tacho stopped working. I had to jumper the FP to GND in the diagnostics connecter under the hood to get the fuel pump to work. I had dríven her the day before in 40+ degree heat without any issues.

I know that the fuel pump issue can be caused by the Circuit Open Relay, but that should not cause the tacho to fail. Later on Friday I removed the jumper from the diagnostics connecter and she started ok, but the tacho is still not working.

Last time something like this happend I had to replace the ignighter module. In that particular case the car was missing badly as it was only running of 2 cylinders.

I have cleaned the grounding point for the group of ground wire under the windscreen washer bottle and made sure the ground lead on thes battery is tight.

Any other suggestions?

Did you sort it, i dont think anyone knows otherwise someone would have a suggestion. I drove mine on that super hot day aswell, can definatley see the difference between hot days and nice cold days with the turbo.

No, still not sorted. So far this is the only real issue......but it could be a sign of a bigger issue waiting to bite me. I plan on uncovering the ECU in the next couple of days and re-seating the wiring harness connections. That has worked on similar issues in the past.

J

As best as I can figure, tacho power comes from the ignitor and the \"meter\" fuse.

good ol mazda manual to help out. though, you pretty much know what to do

Well I fixed the problem today. I bought a 2nd hand ignitor of 'wrecking' Jake and installed it. Everything back to normal...

J

Aren't you running a 'Link'?
What are your dwell times?
Maybe the Link is lunching your ignitor? Is it hot to the touch after a drive?

Maybe the hot day was enough to push it over the edge?

ampz wrote:Aren't you running a 'Link'?
What are your dwell times?
Maybe the Link is lunching your ignitor? Is it hot to the touch after a drive?

Maybe the hot day was enough to push it over the edge?

Yes I am running a FM Link ECU.

Not sure about the dwell times, or the heat.

This is the 2nd time this has happened to me. The cause seems to be the same in that I was having earthing issues with the ECU. In order to resolve these I needed to unplug the wiring loom from the ECU, fix the earthing issue and then plug the ECU wiring loom back in. This meant that I needed to disconnect the negative feed from the battery.

Next time I play around with the ECU I will disconnect the ignitor first.

J