The stuck open thermostat would not cause the problem but a faulty gas cap would as it involves the EVAP system.

the reason I suspect this to be atleast part of the issue is that it happens even more intensely after I get gas-I will have the cap checked by a mechanic(pressure gauge I suspect) or what?

Thanks for the response

Replace the thermostat as well if it is suspect, if stuck open the engine may run to cool and this will affect tune as the coolant temp sensor, fit a new cap and report back what the effect is.

Thanks for the reply-I followed what you recommended to do and it did smooth out substancially-
Thanks Again