I have had an issue with my tach not showing the right RPMS, usually it would just read 1000 to 1500 under any acceleration as long as my foots not to the floor. And it tried to read correct while full throttle through the gears but never fully cought up. And on a few occaisions the tach would actually read right, but only for 5 mins or so of driving, then it would go slow again. Well, i somehow my problem got fixed today. I bumped up the timeing and idle and now the tach works just fine. Can someone explain to me why this is? i have a very basic knowledge about cars and would like to know everything thats going on with my car and why. thanks.

 

Get a aftermarket tach as the factory one is inaccurate.