I bypassed my heater core the other day, drained about 1/2 a gallon out and re-routed the intake manifold output to the radiator, dumped back in the half gallon and went on my way.

The problem:

Now, the engine heats up and just keeps heating up (acording to the guage) goes all the way to the red and then goes down to just under 220* and stays there for the rest of operation. I figured my guage is just weird, it has done things like that before, when winaldl says 170 it reads 220. HOWEVER, i turned the car off when it was up around red line on the guage and the radiator cap was blowing off the pressure, so it actually is getting pretty hot.

I really did not change anything,i dont understand why it is getting so hot, OR why once it does it seems to drop back down to normal.

OH by the way, the fan is operating correctly.

Any Ideas?

 

maybe thermostat is broke

-im not sure, i have the opposite problem.. it takes my car FOREVER to getr up to 100 deg.. let alone 160 where the T-stat opens

i rerouted the hose from the rad-to tpi same as you did, no overheating problems

theres gotta be a sensor or relay or switch thats not operating correctly, for some reason, mabe u bumped it loose or something

 

Did you bleed the system for air bubbles after you reconnected everything?