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For a while now I have been trying to trace a problem with starting my NA8, which is very hard to start cold or hot.

I have been through every conceivable check I can think of and I have listed them below.

ECU = changed
Injector testing and cleaned = fine
Fuel filter = changed
Coil resistance = fine
Spark plugs = tested & changed
Spark plug leads = tested & changed
Cam position sensor = tested & changed
Mass air flow sensor = tested & changed
Throttle position sensor = tested & changed
Fuel pump relay = changed
Injector relay = changed
Clutch pedal switch = changed
Fuel pump = checked with leads in that black box and it runs and runs and runs.

The trick is that even though the the pump runs it does not mean it's pumping. I say that because when I changed the pump the car started instantly.

- battery
- alernator
- starter motor
- compression check
- igniter

I had a pump with intermittent issues. Its been fine since I changed it. I also changed the relay which fixed the issue for a while.

But since you've changed a lot of it. Go for the least expensive options first....

myredmx5 wrote:Fuel pump = checked with leads in that black box and it runs and runs and runs.
The trick is that even though the the pump runs it does not mean it's pumping. I say that because when I changed the pump the car started instantly.

From the above quote it sounds like you've fixed it by replacing the pump, unless it's playing-up again since swapping it over to another pump - or did you put the old pump back in because it seemed to be running ok outside of the tank?
Either way, it sounds like the so called 'blackwire' issue, ie the connectors inside the top of the fuel tank connector block & the fuel pump wires immediately leading from it have degraded so there's a poor electrical connection. If this is the case, & if the pump's ok, testing the pump anywhere other than out of its assembly will show it to be ok, because the issue is in the assembly connector & the wires plugged into it: viewtopic.php?f=55&t=46425

Btw, re igniter NA6 has a standalone igniter, but NA8 doesn't.

Your right 93_Clubman. I changed the fuel pump and all is fine. The old pump still turns out of the tank but I guess it doesn't actually move liquid. I will need to give it a test and see if it actually moves liquid.

The wiring is fine.

Perhaps this is where manga_blue's silting issue comes into play in terms of eventual affect on some fuel pumps (like yours) & wiring connectors (blackwire):

viewtopic.php?f=55&t=46425&p=822568&hilit=fuel+pump#p822568