My 2003 cts keeps turing off as soon as the car engine gets warm

It is possible to swap the 3.2 V-6 for the 5.7 V-8 from the 2004-2007 CTS-V (or Z-6 Corvette). You will need to swap out the engine cradle and you will need to use the 6 speed manual transmission that goes with the V-8 and the exhaust manifolds. You will most likely need to swap the PCM and the rear end too. Also keep in mind that the resale value of your heavily modified CTS will be greatly decreased. It would be far easier and cheaper to just trade your CTS for a CTS-V. I am finding 2005 CTS-V models running $15-19,000 on KBB.

http://en.wikipedia.org/wiki/Cadillac_CTS-V
http://www.kbb.com/cars-for-sale/cars/used-cars/cadillac/cts/?fueltype=g&drive=2wd&engine=8&distance=500

Kelley Blue Book

check coolant sensor and mass air flow sensor

fuel pump

I have 03 cts and service idol control shows when I start the car sometimes and sometimes comes on while driving. I had everything cleaned and everything was good for a week then the engine light would go on and off, I think I may need a new sensor for the idol control or replace it. My question is if I keep driving it will it effect anything else ?

Check fuse, but don't forget the relay!

check your camshaft sensor and try cleaning your maf sensor too

during colder weather, the oil will be somewhat sluggish until it warms up, you may want to change to a thinner viscosity oil during the colder months of the year.

it will byitself just drive it a bit. the valve cover seals or plug tubes need replacing

you probebly need a crank sensor. take it to autozone and have them check the codes they will usually have a history crank sensor code. they usually act up after driving and letting set. the 03 cts uses the same engine as the later model catera. we have seen alot of crank sensor issues