I installed the Mishimoto thermostat,,, OEM Stock EVO thermostat opens at 82 Celsius and the Mishimoto opens at 63 Celsius but since I put it the light from the "check engine" turns on even if I disconect the battery and reset the computer, two or three hours later the "check engine" light turns back on again. But the Evo X has no mechanical failure. Can anyone tell me what this is about?

 

It's because you are never reaching operating temp.

There are a lot of tables in your ECU that will retard your power based on temp. Unless you go through and change your tune drastically, I wouldn't run the Thermostat.

The ECU expects the car to hit 82*.

 

Do you recommend for me to put the OEM Stock EVO thermostat? Or for me to give the ECU re-flash?

 

Your choice, it's your car.

I don't understand the need for the thermostat. But everybody could use a good tune.

 

I wouldn't run the thermostat either...

anything below 75C and the ECU is going to start thinking a bit "chilly" in here

 

Take that thermostat out immediately. It's junk. Your car will switch in and out of warm up, closed, open loop and cause you all sorts of headaches.

If you drive around at night, the coolant will circulate way too early and the engine won't warm up properly. The long term effects on the engine are very bad.

 

That thermostat is good, just like the ralliart... but if you don't build enough heat, not worh it.

 

thank at all

 

Ha, that was the most regretted mod I have every done. Installed Mishimoto thermostat while I was doing coolant reflush. And the problem is engine will not reach working temp while in normal drive. So, engine rpm and SST act odd, but my check engine light was never came up. I installed back to stock one after a week. If you worry about the heat, just use Redline water wetter from Autozone is good enough. I would say install back to stock one (its a pain) and see what happen.

 

Thanks, I'll see what I can do then. I'm going to do what u told me and see what happens

 

I'm glad I saw this! I was about to change mine out to this one. I'll wait until I use the car for a dedicated track car!

 

I was giveing this serious thought until I found this post. Had to do a Google search to find it though.

 

I have the dedicated track car and have this thermostat still sitting in its box. I bought it and am now struggling to figure out why it would be necessary. I suppose there would be a moment when, before the car gets really hot, that the thermostat would open, sooner, then oem. But I also can't imagine a circumstance wherein the car wouldn't get hot enough that the oem wouldn't open (but the Mishimoto would) when actually on the track running hard. So maybe there is a 5 minute period when you are gridding up, or on the track warming up that the Mishimoto could be open and the OEM would not, offering some benefit to cool the car. Do I have this right?

 

interesting

 

OK so I just got off the phone with Mishimoto and from what the tech told me these thermostats are used on a case by case basis. They are for vehicles that are overheating too quickly.

With that being said on my personal car I use an OEM thermostat after trying a lower temp thermostat and finding my car could not get up to operating temps. I do not use radiator fans, just distilled water and water wetter. The car is a road race car only. I do 99% of my races in the South West. There are not a whole lot of applications I could reccomend these for. I am a vendor for these products as well and if you do find yourself in need of one please feel free to contact me for pricing!