The steps so far that I have taken are bypassed the heater core, replaced the thermostat, at 196,800 I replaced the water pump and only 205,883, pulled the radiator and flushed it out, put 1/2 gallon of CLR in the radiator and ran the truck for total of 4 hours idle time then drained the motor and radiator and ran water for 45 min each and alot of trash came out. Put it all back together and still the problem persist. I ordered a head gasket kit thinking that may be the last and final thing to do.
but I would like another opinion. It has had me baffled for 2 weeks now

 

What year and model Cadillac are you working on??

 

It's a 1996 toyota t100. Not a Cadillac