Thermostat Gates or MISHIMOTO

I have a mishimoto thermostat with their radiator setup. It does kick on the fans on at a lower temp range than when the stock one would which is good. I had issues running hot on the stock rad/thermostat and haven't had any issues since.

Man, you just get the thermostat itself. Nothing more. Something like that was for 2008 Rabbit (2.5 I-5). Mine car had exactly same symptoms. It would reach 70 C and maybe at some point 80, but had tendency to stay cool (below 80) when driving. I know thermostat opens at 80 C, so anything below 80 is not quite right.

I got the GATES 34710 Thermostat. I haven't had any problems since replacing it 3 years ago.

I replaced the thermostat with a Mishimoto thermostat and vaccume filled the coolant. I did a 30 min test drive in the 95+ weather with the AC cranked. Never went past the 7th dot.

Forgot to add I test drove her last night to the store, holy $hit it runs like a beast, if I had to guess it feels like it got 20hp back and idles smooth as a new mk7 no shaking no cel lights just butter, it accelerates much smoother and faster then I ever had it. Such a difference it was amaze balls.

By the way, that Gates thermostat (good brand - OEM quality, includes gasket) is $24, delivered, while AutoZone in my area wants $32

mishimoto changed the design of the thermostat when I purchased and you will need shorter bolts they are not provided

we warrantied a Gates thermostat on a pentastar 3.6L three fkn times because the guy said it kept overheating going up hills. Originally replaced for P0128 thermostat code. Then we put an oem part in and it’s never overheated since.

I got a bad mishimoto thermostat with similar results.

I bought and installed a Mishimoto thermostat that activates at 68°C, while my vehicle OEM (Original factory) thermostat activates at 88°C and fully opens at 100°C. With the Mishimoto thermostat (68°C), the coolant temperature basically stays 71 ~ 74°C when driving, from OBDII reading. Short Term Fuel Trim was OK, between -10% and +10%. I checked the spark plugs after one week, they were fine.

However, after three weeks (last Saturday to be precise), the Check Engine Light was on when I started the vehicle, and OBDII gave Code P0128. I searched the code online and got: coolant temperature fails to reach the proper operating temperature, or Coolant Temperature Below Thermostat Regulating Temperature. My thinking was the engine finally realized that the temperature was below the operating temperature, due to the Mishimoto thermostat.