tach/rpm readings
04-14-2009, 10:46 AM
#1
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Join Date: Sep 2005
Location: Wayne NJ
Posts: 1,440
well i was driving the se yesterday and noticed he tach was sitting higher then usual while i was idling but the car sounded the the same as always. i took a look at my pfc commander and found digitally my rpms are normal but the tach reads 500rpm higher then my pfc. what can I do? its not that big of a deal its just a little peevish
thanks
james
thanks
james
04-15-2009, 03:14 PM
#5
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Location: VA
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A generous application of alcohol will fix this.
Seriously, the factory manual has a chart of values at 20 degrees C. The allowable range for actual 1000 rpm is 880 to 1060 rpm. If the tach reads outside this range, replace the tach.
Seriously, the factory manual has a chart of values at 20 degrees C. The allowable range for actual 1000 rpm is 880 to 1060 rpm. If the tach reads outside this range, replace the tach.
04-15-2009, 05:01 PM
#6
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I think it was icemark who told me that the factory tach is adjustable?
here is what he said: Pretty easy to re-calibrate the stock gauge. There is a adjustment pot right on the back of the gauge's sub panel.
both of my FC tachs are way off, I have shift lights in both and just rely on the lights
here is what he said: Pretty easy to re-calibrate the stock gauge. There is a adjustment pot right on the back of the gauge's sub panel.
both of my FC tachs are way off, I have shift lights in both and just rely on the lights
04-15-2009, 05:33 PM
#7
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Originally Posted by Rob x-7' post='920528' date='Apr 15 2009, 06:01 PM
I think it was icemark who told me that the factory tach is adjustable?
here is what he said: Pretty easy to re-calibrate the stock gauge. There is a adjustment pot right on the back of the gauge's sub panel.
both of my FC tachs are way off, I have shift lights in both and just rely on the lights
here is what he said: Pretty easy to re-calibrate the stock gauge. There is a adjustment pot right on the back of the gauge's sub panel.
both of my FC tachs are way off, I have shift lights in both and just rely on the lights
Funny. I went to the factory manual expecting to find a calibration procedure. Based on the info therein, I concluded that there was no adjustment. Erroneously, I suppose.
04-15-2009, 06:35 PM
#9
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Join Date: May 2002
Location: California
Posts: 22,465
there is a little potentiometer on the tach.
if its just a couple hundred off everywhere it might be within the adjustment range
if its 500rpm off at idle, and 3000rpm off at redline, theres something else wrong
if its just a couple hundred off everywhere it might be within the adjustment range
if its 500rpm off at idle, and 3000rpm off at redline, theres something else wrong
04-15-2009, 08:21 PM
#10
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Join Date: Sep 2005
Location: Wayne NJ
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im pretty sure that its only off at idle id notice a 3000rpm difference, i can live with it. its just id like the satisfaction of being abled to look at my tach to see a normal idle out of my now only seven