AaaaHaaaa!!! after replacing my thermostat and having that still not change anything I started to trace all the wires from the coolant temp sensor to the ecu-gauge cluster. Apon tracing the wires I found that the signal wire that goes to the cluster was frayed and grounding out which was sending the wrong signal to the comp. I have sence fixed the problem and my car is back to normal. On a brighter note when I went to the autoparts store I was able to match up the thermostat with another one that opens fully at 160 deg f. instead of the factory 199. Thanks everyone for the info that was given.

 

BadazzCR-

Exactly where was the wire frayed, behind dash or under hood? Was it incident to some of the wiring on your other mods or do we all need to be looking out for this on our cars.

Thanks

 

There are two temp sensors on the evo 8 one for the ecu and one that is a single wire that sends a signal to the gauge cluster. The one that was frayed was the one that goes to your gauge cluster, it can be located on the thermostat housing, if you look just below the upper rad. hose you will see a one wire sensor. My wire frayed on this sensor about four inches from the plug. You can see if you look at it that there is a metal braket there, my only guess is that Mitsu didn't put enough thought into protecting this wire. Hope this could be of help.

 

So what your saying is the car wasn't actually overheating but the gauge was grouding out and running up to hot.

 

Correct, the car actually never got hot. Just the wire to the gauge was grounding out sending a false signal

 

Well that is the best of both then. You found the problem and your car never got hot.

 

dont buy the 160 degree thermo. the car will never run at its optimum if that was hooked up. I'd run the Ralliart one that opens a few degrees before the ****shubishi one does

 

Almost all aftermarket thermostats have smaller openings than Mitsubishi ones.

I wouldn't run one.

I certainly wouldn't run a 160F thermostat! The car will never warm up, and your gas milage will suffer, as will performance.

 

yes, listen to Shape n' I! =)

 

I just put a PWR radiator and a 160 degree thermostat in my Supra. I'll probably do the same to the Evo. I'm sorry but I'll do everything possible to keep my head cool. Cool head = less risk of detonation = higher boost / safer boost.

Now if the size of the passage is smaller than the stock one it may be a wash - but my TRD was the same size passage.

 

agreed... sounds like your running too lean.

 

I bet he is not running lean. The gauge wire was grounding out. Look at he posts.

 

yeah I saw that after I posted.

 

Actually, I've found that a hot head can make more power than a cool one. Obviously there is a range where it is most effective. But I'm certain that it isn't as low as 160F.

 

I agree with ShapeGSX, an engine is effectively a heat pump. More heat (to an extent) means more power. It's plain and simple.
The internal combustion is there to create heat and expand, thereby making power. Why do you think the high hp engines need more cooling. 160 thermos are out there for when your making alot of power and need it just to get in operating range.