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OK, this me has me stumped and I would really like some suggestions.

I have a 2000 model NB8A. Last week it wouldn't start, although it cranked over as normal, just no starting.

I have followed a number of guides to diagnosing the problem and, so far, everything passes the tests.

One thing that I noticed was that the tacho didn't move when cranking and that lead me to think of the cam sensor and the crank sensor.

I pulled them and tested both. Both appeared to work, although the crank one only gave about 0.75V when metal passed near it. I swapped this (the crank sensor) out.

There is still no starting. Just cranking, with no tacho movement. I should probably add, no spark.

So, any advice?

Nick

Is that after you have dríven it for awhile or starting up when cold?

Well, it was after the car had been left for about 4 hours. So it was cold.
I can still not start it after another 4 days of the diagnostics and getting parts.

Nick

Fuel?
Got some?

Yes, lots of fuel.

OK, the diagnostics.

Immobiliser isn't the problem (light flashes and goes out)
Checked the timing belt isn't broken.
Check engine light doesn't light up when the ignition is turned on.
Checked the main EIF relay (green one in the engine bay)
Checked the relays under the dash and checked that I get 12V to the ECU (pin a1)
Fuel pump relay is fine.
Fuel pump runs.
Changed the fuel filter.
Fuel tank has lots of fuel (>40l)
Fuel comes though the lines.
No spark from any plug.
Checked all the fuses under the dash and in the engine bay.

Nick

Lack of ignition (spark) assuming plugs are OK and ignition power is getting to fuel pump etc.: fuses, coils, leads, CAS, wiring detached.

In the good old days and even with things like lawn mowers probably the first thing to check is spark. It will not be plugs.

My NB8A also has some fuses right up under the dash near the steering column, I think they're used by the alarm. Might also help to check those.

Cam sensor?
Crank sensor?

Easiest way is to borrow someone else's sensor and swap for yours, starting with cam sensor, then crank.

Buy a noid light and plug it into an injector. No light no injector signal, possible failed can angle sensor! Are the plugs wet with fuel when you crank?

Noid lights are cheap and a quick way to diagnose or eliminate a problem.

http://www.tridon.com.au/Products/Product.aspx?SG=5&S=21&G=622&P=68586

Reread Nicks list- the problem is no spark- he listed it.

EGI/Main relay? It's the green one in the engine bay fuse box.

I had same problem in mine a few months ago. I changed the crank angle sensor and seemed to fix it but it started doing similar things only a little while later. Replaced cam sensor and its been fine ever since. I did also buy a new EGI relay but it made no difference to my car.

How can an engine run without spark?

Mr Morlock wrote:How can an engine run without spark?

A diesel engine can.