I am getting scared of summer for strange reasons.. My maxima stalling...if temp goes above 70 degrees outside..

It happened today again... I drove around 14 miles contuniously... luckily it didnot stop on the main road but on my apt parking lot..in the end..

Other wise my maxima is fit and fine.. runs like a champ

Here is the thing
End of 15 mile drive engine is slightly shaking ...the RPMs jump little up and down. Some what like one struggling to breath. This happens for 5-7 minutes.. This happend while I put auto in parking...
Then I see the exaust.. there is put put going on ... put put..it is clearly audible...
Then it gives up...it shutts off.

Now if I leave the car for 45 minutes it will run fine.. you wont see any of the stuff till you drive another 15 miles...

Now I am wondering what could be wrong..!!
I havent checked/changed catalytic converter ...is it possible that there is some blocking at high temperature... and that is why I hear this put put on exaust..

How many miles do you thing think stock cat converter might last..?
My car has 73K miles. And this thing happened 2-3 times last summer... In winter it had no problems...!!!!

Please some one help me... to have a problem free summer with may maxima this year!!!
I have replaced fuel pump,filter,air filter, pcv, O2 sensor and cleaned throttle body, IACV valve..

 

Two words-Ignition Coils. Good luck. Many of us have the same problem and the latest word is that one of the 6 Ignition Coils is shot. Buy a used one and swap em out-that's what I am gonna do.