should also turn your car on, keep ALL accesories,(stereo, fan, etc) off! Let the car idle for about 30 minutes. Turn car off and then start it up again.
Need some advice . i have a 5 speed Mazda prtege 1.6 2000 with no rpm gauge so i bought a dash with one on it. heres the problem. plugged in everything but the rpm gauge doesn't work. told the dealer to change the ecu. but most the ecu's i've found are for a 1.8 mazda protege 2000. can that work or just forget it, and keep listening to the engine?????