I have a 2005 Evo 8 with about 88k, I just recently had a shop replace the crank position sensor. Driving my vehicle from the shop to my job, as I got closer to my job, i noticed the temp gauge starts going. The fans turn on, the coolant reservoir has coolant, and I don't think its the head gasket, no white smoke. I replaced the oem radiator about 2 years ago to a mishimoto. Any suggestions? Thank you for any help in advance

 

does the radiator have coolant?

 

Make sure thermostat is working and coolant is bleed. How's it drive beside the heat issue? Did the shop remove timing belt to do the crank sensor?

 

Since engine coolant temperature varies a large amount depending on engine load, Mitsubishi installed a lying gauge. It reads normal over a wide range of temperatures and only reads hot only if really hot. The normal symptom of a blown head gasket is the coolant reservoir filling excessively or overflowing. So, this requires immediate attention. Change the thermostat, change the pressure cap, make sure the radiator is full, make sure the reservoir is full to the full mark and keep checking the reservoir for boiling or overfilling. If it is the head gasket the problem may only occur when the head lifts at full boost.

 

/\/\ this BTW be sure the temp sensor wire is clean . its under the top hose going to t-stat housing

 

More than likely your thermostats stuck in the close position. you can remove it since it is summertime and see if the Evo overheat or not.