As I was driving yesterday, I noticed that my tachometer wasn't fully functioning correctly. I have a 5 spd 2000 GXE and I was pushing it yesterday, but I noticed that my tach only goes up 3400 rpm and no higher. The car isn't struggling or anything, it moves as normal, but the tach just won't go above 3400. I was idleing at a light and revved it, but it works fine up 3400 and stops there until i left off the gas and it will drop back down to idle speed. Does anyone know what might be the cause of this? Thanks in advance.

 

Its probably going to be in your tach guage if the vehicle runs normal.

 

Has anyone had to replace their tach before? I really don't know how a tach works in correspondence to the engine speed, but I would imagine that the tach in the instrument cluster shouldn't be too difficult to replace, but what about the "sensor" or whatever the tach uses to read the engine speed? I would imagine that it would be difficult to fix. Would anyone care to shed some of their knowledge or experience on this matter? Thanks.

 

My guess is that the tach is physically sticking. If there is/was a sensor problem, the car would not run correctly and you would likely gete an SES light.

In short, a magnet is attached to a sensor and that magnet reports a frequency to the ECU, thus giving RPM feedback. This is a vital function not only for the tach, but for other systems in the car (electronic/driveability. And since you say the car drives fine, my guess is that the you can rule our sensor/electronics.

If I were you, I'd locate a 'How To' for changing gauges and use it as a blueprint for diagnosing your problem (sticking tach needle i.e. take dash aprt and see if the needle is sticking.