According to my ScanTool the coolant temperature sensor reads 235-245 at operating temperature on my TPI 305. The factory gauge reads normal, about 190-200, my Autometer gauge reads 180-185 ish, the coolant is full and the dual fans are running(Ramchargers). This has me led to believe the CTS is likely faulty, is that a fair assumption? The ScanTool reads its in closed loop, no other codes except an intermittent EGR code 32(2 year old GM valve/switch). The car runs fine cold but after a couple minutes it will act like there is a miss or stutter under throttle, or possibly with the higher than normal CTS its dumping more fuel in than there should be. Almost all of the ignition parts are new(plugs/wires/ignition module/coil/cap/rotor) and fuel pressure reads between 36-38psi at idle. I thought a bad CTS would throw a code typically....has anyone else experienced or heard of this symptom?

I purchased a new CTS and am about to replace it anyway, but not sure if I'm giving myself false hope that it will be the fix.

 

when they decide to go south I have read on hear that they tend to show one extreme or another. SO either really rich running occurs or really lean.

My Dads 305 TBI , did exactley what your symptoms are. Ran great cold ( more fuel in their ) then crapped out when warm ( too rich for the warmer engine)

 

Also when replacing the cts also replace the plug. They can sometimes get a bad connection. my cts went out and that is what i replaced. ran fine and now i have a miss i cant figure out.