Kugawestie's MX5 SDV Build Thread - Now An Upgrade Thread

[KugaWestie]

Sorted out a bit more of the loom onto the engine tonight, and then decided to become a bit braver, so I stripped out some of the headlight pop up wiring

I also need some help with manifolds, I have started a thread in techie talk

Click here

Any help appreciated!

[KugaWestie]

Well, I decided to bite the bullet tonight and start to swap over the inlet manifolds.

I got the manifold off fairly easily, but the new gasket that had been fitted did not want to play the recycle game, so I have had to order another new one.

In the meantime, I cleaned up the inlet manifold that will be fitted, and laid it on the side of the engine temporarily.

I have also been doing some more work on the loom, and have now stripped out some of the audio and heater wiring.

I have also relocated the radiator fan sensor the the front of the engine, which meant extending the wiring

I also re-located the header tank pipe underneath the chassis braces after a bit of pipe bending, which gives a bit more clearance for the water temperature gauge sender.

Lastly, I managed to get the blanking cap off the unused exhaust manifold (after a 20 hour WD40 soaking) and fit this to the manifold in the car

[KugaWestie]

Picked up the new inlet manifold gasket today, so I completed the refit of that tonight  

The wiring loom is doing my head in though  

[KugaWestie]

I had recently found some countersunk M8 bolts, so swapped these over on the handbrake fixings today to help with propshaft clearance

I then carried on with the wiring loom, I think I have stripped everything out apart from about 6 cables that I am unsure about. Also fixed the ECU plate and fitted the ECU to it. New battery cables have been put into place and connected into the car.

I then started to have a look at the dashboard wiring, but have two problems, the connectors dont seem to fit in the Mazda dash, which although I am not using this, confuses me

Secondly, the wires dont seem to correspond with my wiring diagram, so more confusion!

[KugaWestie]

The dashboard wiring connector issue has been resolved - I am missing a section of loom! Fortunately smokey mow has come to the rescue and has posted me a section of loom today - Many thanks  

This morning I have been in the garage with a mission to start the engine.

So I:-

Connected the earth for the engine.

Temporary rigged up the coolant header tank and filled the system with water/antifreeze.

Then I filled the engine with oil.

Took the old spark plugs out and fitted new ones.

Put some fuel in the tank.

Connected the battery.

The engine turns over lovely, and fires for about a second, then stops again.

I have done the Diagnostics check to make sure the fuel pump is running/primed the fuel system, and this seems fine.

Any ideas guys?

[TIG Brother]

This might sound a bit funny but mine would do the same if I left the fuel cap off.

[KugaWestie]

This might sound a bit funny but mine would do the same if I left the fuel cap off.

At the moment I have got a polythene bag on the fuel tank and then the red plastic cover over that, sandwiching the bag in - what do you think?

[hilux]

Sounds like a sensor or relay timer may be holding it back, check power and continuity to them.

If its fuel injected sealing a tank wont help surely as its the low pressure side and the tank vents anyway to replace lost fluid?

[KugaWestie]

Fuel cap makes no difference, worth a try

I am getting power to the coil pack with ignition on.

I have taken a fuel injection wiring connection off, and established that with ignition on, there is no power, on cranking the engine, there is power, so this seems to be the problem, no power to the injectors with ignition on.

Any ideas anyone?

[TIG Brother]

Just starting with the basics first, can you hear the fuel pump fire up when you turn on the ignition? And is it staying on once you are running for the few seconds ?

[KugaWestie]

Just starting with the basics first, can you hear the fuel pump fire up when you turn on the ignition? And is it staying on once you are running for the few seconds ?

Yeah fuel pump is running, can't hear it when engine fires briefly due to exhaust noise, buti have run the fuel priming exercise using the diagnostics, and also left the override in place whilst firing up

[TIG Brother]

Ok. Plugs out Out and rested on some thing to check for spark? And then fuel injectors. Sounds like a relay or some thing is playing up.

[Mooch]

Gary, TBH I don't know what the fault is, but I did have the same problem which was solved by accident.  

I had cut back and insulated the right hand cluster of wires feeding the pop up headlights etc and was pretty sure that nothing vital had been cut out at the same time.  I was fiddling about looking for an earth for something else and used what I thought was a redundant earth wire from this bundle.  Oddly enough, when reconnected to earth, I got a 'click' which turned out to be a vital relay somewhere up in the injector or ignition pack area.  This was the reason the engine wouldn't fire.

My suggestion would be to identify all the earth wires in this stripped back section and test them to earth to see what happens.  Not very scientific, but it worked for me.

Good luck - HTH

[hilux]

Fuel cap makes no difference, worth a try

I am getting power to the coil pack with ignition on.

I have taken a fuel injection wiring connection off, and established that with ignition on, there is no power, on cranking the engine, there is power, so this seems to be the problem, no power to the injectors with ignition on.

Any ideas anyone?

Check the relay that supplies power to the injectors is wired correctly

It might be the crank sensor as this tells the injectors to fire when it sees sufficient revs - equally is the starter turning it over at sufficient speed to tell the ECU to fire the injectors?

[KugaWestie]

Not had much time since this morning, so intend to get back on it tomorrow sometime.

It will be spark plugs out and then go from there.

I have also discovered that there is no purge solenoid valve connected to the loom, not sure if this will make much difference.

Video of the current situation

Video