I telling you ITS THE IMMOBILIZER............. If its cranking but no ignition and no sign of a spark. Its the immobilizer...... Disconnect it..
Pretty sure its not. As they can get the car started and it appears when it gets to operating temp it goes into safety mode, fouls the plugs and then stops and won't restart.
Could be over fuelled and being flooded. Does the fuel pressure stay high after its turned off? the fuel rail should stay pressurized for hours a after the cars turned off. If it drops away quickly after its turned off the injector orings could be shot or an injector RS... Try to start it with your foot flat to the floor and make the ECU go into flood start mode.
Thanks. Fuel issue was one the first things I thought it might be but we have good fuel pressure an the injectors are brand new nismo 550s. It is running a Walbro Fuel pump through a standard regulator, but that was how it was before the rebuild and had no issue then. I suppose we will just have to keep looking but holy cr$p this car just doesn't want to play nice.
Was the replacement sensor OEM or aftermarket? You can remove the coolant sensor and heat up some water on the stove with an accurate thermometer and check the sensor that way. that can be the cause of flooding. On page EF & EC 178 of service manual it states. At 20 C Resistance 2.1KOhms (2100Ohms) to 2.9KOhms (2900Ohms) At 50C 680Ohms - 1000Ohms At 80C 300Ohms - 330Ohms The fact that you have no spark or sometimes you do is puzzling. You need someone to check from ECU to PTU to coil packs with a meter. Question is is it an ignition or fuel issue. The fuel issue is easy to check as has already been suggested but only if you can get the motor going in the first place. if it starts the stalls hold accelerator pedal down fully and if it starts then stalls it is flooding. Check the coolant sensor. If you cannot start it and there is no spark then the ignition circuit needs to be diagnosed by someone who knows the zeds, how to use a multimeter and read wiring schematics. Michael Z
