after twenty or so minutes......

why would my car start to diesel....and I have to let it cool down again before i can drive it...but in the evening I can drive it forever and its fine....only during the day...which in Palm Springs....Heat....Sun...the temp runs at 230 which is 30 degrees hotter with my new thermostat........Thanks for any help....

your car is dieseling because it's running hotter, you shouldn't get a thermostat that opens at a different temp than OEM specs but if you do you should know what your doing and I wouldn't see much reason why you want the car to run hotter in the summer...winter maybe to get more heat faster but not much reason in summer...you can run higher octane gas which will probably help a bit but 230 is a hot engine and that hot is bad. Heat leads to shorter engine life, and more problems sooner.

nope changing the temp. rating on a thermostat wont do anything but do more harm.. since the computer is set to run at that temp so if its always open and temp dont work then it will run more rich and so on.. always use the oem spec unless the ecm is modified..

Next make sure your overflow tank cap is good or just buy a new one... next im betting you have alot of air in the system.. use the bleeder screw to remove ALL! the air out if you dont know you get air pockets and then hot spots form and then the water pump wont work right and sensor gets false readings and so on.
The bleeder screw is located on top of where the water pump .. make sure the air is out and you have the heat on full while doing this