The car is a completely stock 2004 touring auto with 40k or so miles on it.

This all started happening yesterday. The car has three separate scenarios that happens when trying to start it.

1. It starts and runs fine (one out of ten times)

2. it wont start at all, just crank

3. it starts but it takes a while, and when it is running none of the gauges work, the a/c blows but not cold, the slip and tcs lights are on, and the transmission shifts incredibly hard. (this is what happens most of the time)

There has not been anything done to the car lately.

It was taken to the dealer and they scanned it but could not figure it out and want another $500 to do more test.

Please, some Z guru help me.

 

Did the dealership pull the codes? If so post them

 

I have seen problems like this before on a G35 this one would not start however... there is relay that supplies ground to the PCM if that ground is not supplied none of the sensors get switched on. I was able to temporarily fix the problem by running a wire to that particular pin out on the PCM and the customer was able to drive his car to the dealer for PCM replacement. See if you can get any DTC's from the dealer or your local parts store. Post what codes are thrown and we can go from there.