I just recently replaced my z6 with a y7 for temporary driving....used everything off the z6 motor (IM, alt., starter, tranny, etc.)...

The problem: After the car is warmed up to regular operating temps, as I'm driving the temp needle drops to cold and fluctuates up and down between the normal level and cold...when I'm at a stop and idling, the needle returns back to the normal level until i start driving again...

I have a small leak near the top of my radiator where the upper hose goes, but could that cause this fluctuation?...its just a sewing needle size leak...

I replaced the thermostat, and checked all hoses for additional leaks, and it all checks out fine...

Could it be that i'm using an OBD-1 harness on an OBD-2 motor? the temp sensor plugs are the same...so could it be broken on the y7?

Any suggestions or solutions would help...thanks

 

bump...anyone???

 

bump again