Why is my tachometer reading wrong?
An insufficient power or ground will cause a tachometer to actually read too high. If you are experiencing this problem, perform the following: Using a voltmeter (not a test light), measure across the Red wire and Black wire coming from the tachometer while the engine is running.
How do you test tach output?
Set the meter to AC voltage. Connect the negative Meter lead to a good chassis ground in the vehicle and the positive lead to the suspected tachometer wire. Start the vehicle and wait for it to idle down to normal idle speed. At this point the meter should be displaying a fairly constant AC voltage.
Why is my tach bouncing?
Usually a loose or failing switch will also cause the car to run poorly, but if the problem is very minor it can begin as an erratic tach signal. Look for corrosion, a broken wire, or a loose connection anywhere between the coil terminal and the tachometer.
How do I know if my tachometer is bad?
There are typically four problems that can occur with the tach: it is totally inoperative and always displays zero; the needle is stuck or permanently pegged; the needle is erratic; or the RPMs are consistently off – either low or high. To test the tachometer, you will need a digital multimeter.
How do you wire a SunPro tach test?
Insert the dimmer switch wire into one side of the splice and the white wire coming from the tachometer into the other side. Connect the green wire to the negative side of the ignition coil. The ignition coil terminal may be listed as “TACH”, “TACH TEST”, “DEC” or “ECU” terminal. Use this connection on vehicles with a distributor.
Where does the green wire go on a tach?
Connect the green wire to the negative side of the ignition coil. The ignition coil terminal may be listed as “TACH”, “TACH TEST”, “DEC” or “ECU” terminal. Use this connection on vehicles with a distributor. Connect the green wire to the tachometer output lead on vehicles that have distributor-less ignition systems.
Which is the latest version of the Sun tach?
Here’s a look at Sun’s latest SST802R tach. If you turn back the clock, you’ll recognize this. It’s a dead-ringer for the original Super Tach that was near and dear to the hearts of many folks of the high performance car persuasion.
Are there still any Sun tachometers out there?
Over the years, time passed by the vintage Sun tachometers. Sadly, they were eventually discontinued. But then something happened. Retro became new news. The folks from Sunpro recognized the potential. Both the FZ model tachs and Super Tach were retooled and re-released.