tachometer not correct
10-16-2012, 04:56 PM
#1
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Year: 1996
Model: Cherokee
Engine: 4.0L
tachometer not correct
Ok so ive spent alot of time trying to track down Why i was having a high idle isue. I finaly got a hold of a scanner and it told me it was running at 700 rpm but the tach was reading 1100! what could be causing this?
10-16-2012, 07:44 PM
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Year: 1996
Model: Cherokee
Engine: 4.0L
No i hooked up to a computer scanner to read my codes(o2 sensor) and it read 700 rpm. So the engines idling properly. But the tach ever since ive owned it has read 1100 RPM. Ive been trying to track down a vacum leak that doesnt exist. :/
Im just trying to find a good place to start
Im just trying to find a good place to start
10-17-2012, 01:17 AM
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Model: Cherokee
The tach is just a voltmeter, with a frequency-to-voltage converter that converts incoming ignition pulses to a voltage to drive the needle. On the back should be a calibration trimpot. Pull the cluster and take a look.
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