everything worked perfect before, but now my temp gauge, the stock one, right above the gas gauge is not working anymore. The needle just sits at the bottom. It was working fine after i installed some bolt ons, but then, i installed a mbc and put my ecu back after it was flashed... i tought there might be a fuse for the temp gauge, but could not locate one. no check engine light and everything else works fine. any suggestions would be awesome... i don't know if i want to take it to the dealership either, but i might have to.

You may have knocked the sending unit loose. Not sure exactly where its at, but probably somewhere close to wherever you tapped in the MBC. I would check for anything obvious.

You may also have blown a fuse when you plugged the ECU back in. Did you disconnect the battery? There are lots of fuses other than the ones under the dash. It may be one in the engine compartment. Its the black box near the intake.

i've checked both fuse boxes, none of the diagrams say anything about the temp gauge. thanks though. can anyone else help?

just tap it, mine does the same, tap it, and it works.

i've already tried that? anyone else

Tap it harder.. REAL hard...

just cause you cant find the fuse on a diagram check all the fuses anyways... usually you can see if they are blown without removing them... or just remove them one by one and check

Find out where the sending unit is and check it!

Anyone? Someone with a service manual???

Check all the electrical connectors near the water neck housing (the one that connects to the upper radiator hose). That's where the water temp sensor is.

Like sr20 stated:

Check the sending unit for the temp gauge. It should be located around the T-stat housing.
Just follow the upper radiator hose and that's where the T-stat is located.

Check all of the sensors around there if they are still plugged in.

BTW....what kinda bolt-on's were you installing before this happened?