Hi evo m, I just had the themostat, temperature sensor and temperature sender replaced on my 2004 evo 8, when I had my timing belt done. Buuuut my water or coolant temp gauge, on the cluster, still fails to work properly. It was about 10-15 degrees Fahrenheit when I started the car this morning and the gauge goes to dead center on the temp gauge, while the car is ice cold. Then as the car begins to warm up, the needle rises until it reaches the "hot" mark at operating temp. I know the car is not overheating because I hooked it up to my obd2 scanner and the coolant temp ranges from 80-82 degrees celcius, which ranges roughly from 170-180 degrees Fahrenheit. So it is almost like the gauge is functioning properly but instead of starting at "cold" it starts at the middle of the gauge. I have seen many discussions about these types of problems on evom but none quite like this. The guys at the shop told me that the turbo timer(which the previous owner had installed) may be spliced into a certain wire that is throwing the gauge off. Like maybe the voltage is off for that gauge or something? Well I am certainly no mechanic or wiring expert so I am not sure what is going on here. Should I just remove the turbo timer and start there? Do you think the gauge is faulty? If any of you guys have ideas that would be greatly appreciated. I want to get this problem sorted out soon. Thanks for reading my essay haha -Brian

 

Check the ground that goes from the intake to the firewall ..
I was having the same problem👍👍👍

 

Hey man thanks for the reply!! Where exactly is this ground located? And is it running from like at maf? Like that intake? Sorry if these are dumb questions haha