Posted a while ago and the problem is still not sorted. Here are the basics.

 

First start of the day the car struggles to start. It cranks and will start but really rough and then stall after a couple of secs if not immediately. After a couple more attempts it is absolutely fine and remains fine for the rest of the day. It appears that this only happens when the car is stood for 12 hours plus.

 

When I try and crank it first thing in the morning, the Speedo needle spikes and jumps around.

 

Anyone any ideas??

possiblr ptu fault, do you get any smoke out of exhausts when starting up

except for the needle bouncing around mine "started" the same way, Turned out to be the ECU temp sensor. ECU diagnostic didn´t reveal the fault either, had to measure the resistance between the connectors to discover the sensor had an intermediate problem and when cold would tell the ECU the engine was overheating and while trying to start her up from cold would overfuel the engine.

 

worth a try

 

:)

try cleaning up all the obvious connectors and see what happens mate

go to the 300zx manual and engine management etc page 42, it has all the diagnostics tests that you could ever need!!