 tachometer question, I'm learning so much about FI and points |
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| brant |
 Apr 4 2004, 12:40 AM
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914 Wizard  Group: Members Posts: 11,951 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
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Ok..
I should know this but I don't .... I spent the day getting a car running... not driving, just running on the jack stands... I finally go the wiring sorted out, got the tach working and she starts right up... problem is: at an idle of around 1200rpm.. the tach is reading 2500rpm... WHY? is this a dwell issue or something? I really think I have the wiring straight.. so would it be the tach itself failing? I dunno (I'm so not used to having points and FI.... I'm learning a lot) brant |
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| ArtechnikA |
Apr 4 2004, 07:28 AM
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rich herzog Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None |
QUOTE(brant @ Apr 3 2004, 10:40 PM) problem is: at an idle of around 1200rpm.. the tach is reading 2500rpm... is it a constant 1200 rpm error, or is it a constant 2X error ? is it an unmolested OEM tach? 'cause it sounds like it might have been modified for V8 use (V8's have twice as many ignition events per rev as we do ... -- except i'd think it'd read halfspeed, rather than 2X... -- so nevermind...) if it's a constant additive-type error, could be wonky grounding. for a multiplicative error, could be that, i s'pose, or -- well, i don't know what else. there doesn't seem to be any lack of 914/4 tachs to check out with a known good one... make sure the tach wire isn't running right past any plug wires - especially the coil wire - that can confuse them ... are your plug wires in really good shape ? |
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Posts in this topic
brant tachometer question Apr 4 2004, 12:40 AM
brant good idea about the plug wires...
I don't thin... Apr 4 2004, 08:35 AM |
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