[Lvcoyote]

There is no way you can go from a normal temp to overheating in less than a second as the OP states is happening. I'm thinking Temp Sending unit is bad. Also either use the Genuine Nissan oil filer, WIX, or Mobil 1 filters seem to be a popular choice as well.

 

[Lvcoyote]

Then it sounds like you need to take it to someone that does.....

 

[Lvcoyote]

I still think the problem is the temp sensor/sending unit......

 

[Lvcoyote]

Are you getting coolant in the engine oil??

 

[Lvcoyote]

Which cap, the one on the radiator or the one on the overflow? Hopefully they put the right cap on it if it was the radiator one.