I have a 97 sts and it is not starting correctly. Basically when the car is cold it starts great 1 turn and vroom. but once it gets warm it is harder to start. it takes like twenty cranks to start then it fires ups drops dow to 200 rpm and back up too regular operating rpm..could this be because of the antifreeze i am using or a cts sensor that is about to go bad. the fuel pressure is fine any thoghts please i need some mechanical assistance.:mad: :eek::confused:

Sounds like the classic symptoms of a bad FPR (Fuel Pressure Regulator). Take off the beauty cover, then turn the engine on and take the vacuum hose off of the FPR. If you see fuel come out of the nipple on the FPR or the vacuum hose, the FPR is bad. Be ready when you take off the vacuum hose though because the idle speed will run away.

Also Have you checked the codes?