I have a problem with my Nissan Micra '95. Engine works perfectly (no stalls, powe cut-offs), until warmed. After it has reached optimal temperature (5-10 min.dashboard indicator) it suddenly goes down and I cannot start it again until chilled! I'm sure that it's not overheated and all the rest of equipment works fine (lights, radio, etc. no warnings on dashboard). Have changed ignition cables just in case, but it did'n help. Please help me out there, I got stuck in Sweden and don't know anyone here!!!
Get it hot and let it die, then check for a poor connection somewhere, pull each multiplug apart and spray with some wd40 or similar and reconnect, especially hunt out the crankshaft sensor connections.
After remaking each connection see if it will start. If the MIL light flashes with the engine running at idle then you will need to read the codes in the ecm. to do this: switch ign on, bridge data link connectors CHK and IGN (6 and 7)(this is the connector below the fuses), wait two seconds, remove bridge wire, count flashes from the MIL light, Long flashes are tens, short are units. Long pause separates codes.
If it is an electrical problem then my premonition would be crank sensor.
Try running it with the fuel cap off. It's possible that the breather to the tank is blocked and the pump can't suck any more out of it due to a partial vacuum. This would give you the symptoms you've got, only instead of it being cured by the engine cooling off it's cured by air slowly leaking back in.
If it is, then when the engine cuts out, you should loose fuel and spark.
Checking for spark is simple enough. Put a spare spark plug in an HT lead, and while holding the plug against the cylinder head (using some insulated pliers), get someone to crank the engine over. If you get a good spark, then problem lies in the fuel system somewhere.
Checking for fuel is more tricky, and will depend on the type off injection system. If it's multi-point injection (there'll be an injector in each branch off the inlet manifold, just before it bolts onto the cylinder head, with a fuel rail connected to all off them). Then you might be able to hear/feel the injectors clicking when the engine is cranked over. Check to see if you can feel the injectors clicking when the engine is idling, before it cuts out. If you can't feel them, you'll need to rig up a test lamp, and connect it inplace off one injector. When cranking the test lamp should flash.
If it's single-point/throttle body injection, the fuel pipes will connect near to where the throttle (butterfly) valve is. If you remove the air inlet pipe to the throttle body, with the engine running or cranking, you should be able to see/hear the fuel being injected.
If no fuel is being injected, it could be the fuel pump (unlikely as when most fuel pumps fail, they don't come back to life). Only way to safely check this, is using a fuel pressure gauge.
If you get no spark and no fuel, then it's most likely the crankshaft position sensor. Bad connections generally cause more random problems that aren't affected by heat.
The 3 most recent Nissans I've owned all gave a sucking noise when the cap was removed so I would say it's normal. It could still be the problem though if there's more of a vacuum than is typical.
At the moment it doesn't matter where the breather is. If you remove the cap you won't need a breather and you will discover whether this is the fault or not.
I believe that modern fuel systems arrange for a slight level of vacuum in the tank in order to prevent spillage if the vehicle overturns. But obviously, not too much.
Sounds like an overheated something, crank sensor or ignition pack. If there's no fault codes stored you could try using a can of freezer spray from an electronics shop on them & see if that temporarily cures it.
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