Odd problem: Tach reading is 'half' of what it should be.
06-15-07, 11:53 AM
#1
Odd problem: Tach reading is 'half' of what it should be.
This problem had me going in circles for the last week, so let's see if we can figure this out:
My tachometer readings are litterally "half" of what it should be, meaning that at idle, 750-800 rpm, it reads about 400. At about 2500 RPM, the tach reads at about 1300 RPM.
I have a Microtech LT8, so I was using the tach readings from that, which are indeed correct.
What could be the problem? I have not tampered with the stock tach wire that goes to the trailings. The car is an 87 TII that drives and runs beautifully.
My tachometer readings are litterally "half" of what it should be, meaning that at idle, 750-800 rpm, it reads about 400. At about 2500 RPM, the tach reads at about 1300 RPM.
I have a Microtech LT8, so I was using the tach readings from that, which are indeed correct.
What could be the problem? I have not tampered with the stock tach wire that goes to the trailings. The car is an 87 TII that drives and runs beautifully.
06-15-07, 12:10 PM
#3
Automatic = Power drain
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You may have lost the connection on a resistor or capacitor on the circuit board for the tach. The tachs can be recallibrated for a v6 (now they are calibrated for a four cylinder.) (Yours appears to be calibrated for a V8.)
06-15-07, 03:55 PM
#6
marky
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This problem had me going in circles for the last week, so let's see if we can figure this out:
My tachometer readings are litterally "half" of what it should be, meaning that at idle, 750-800 rpm, it reads about 400. At about 2500 RPM, the tach reads at about 1300 RPM.
I have a Microtech LT8, so I was using the tach readings from that, which are indeed correct.
What could be the problem? I have not tampered with the stock tach wire that goes to the trailings. The car is an 87 TII that drives and runs beautifully.
My tachometer readings are litterally "half" of what it should be, meaning that at idle, 750-800 rpm, it reads about 400. At about 2500 RPM, the tach reads at about 1300 RPM.
I have a Microtech LT8, so I was using the tach readings from that, which are indeed correct.
What could be the problem? I have not tampered with the stock tach wire that goes to the trailings. The car is an 87 TII that drives and runs beautifully.
Perhaps you should purchase a subtle aftermarket tach that displays the reading from the Microtech? It'd be more accurate anyway.
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