Tach problem

EZMachN · 07-22-2006, 09:23 PM

I installed my Auto Gauge tach tonight. And its not working. The green wire is in the MSD 6al Tach Output slot, Red is in fuse #11(radio), Black grounded, and White into fuse #13 (Illumination). The needle just sits on the shift point and won't move. Does this sound like I need a tach adapter or need to do some rewiring?

Blown 5.0 · 07-23-2006, 07:30 AM

Running off the msd you shouldnt need a adapter. I would check ground and be sure i have ground, most of the stuff in and around the dash is plastic, may be nessary to just run a temp. wire from ground and hot battery just for checking purpurse. does the needle move any at all? Does key on and key off make any differnce? May have a bad tach. Hope this helps

EZMachN · 07-23-2006, 11:03 AM

I have the ground ran through my firewall onto the fenderwell. Once cranked I can turn the needle with the shift set knob, but it won't go past 1k rpms, it stops there

EZMachN · 07-23-2006, 11:13 AM

It is getting power from the key on, b/c once key is on(not cranked) it will move to the previous shift point. Once cranked it drops to 0 then shoots to 5k(shift light point) and sit there. Which makes me think either need adapter or broken tach

Blown 5.0 · 07-23-2006, 05:18 PM

Broken Tach

EZMachN · 07-24-2006, 05:57 PM

Bought a $185 Auto Meter Sport Compact today. Still don't work

I'm thinking its the damn MSD?

04 Mach1 · 07-24-2006, 06:47 PM

Hook the tach signal wire to the neg side of the coil that way you know you have a signal. The tach output on the msd 6al might be burntup.

EZMachN · 07-24-2006, 08:58 PM

Yea, I ran a voltometer(sp?) to the tach output and was getting negative reading. And you can't run the tach to negative coil with MSD b/c it will fry it up and void warranty.

Italian LX · 07-24-2006, 09:28 PM

Quote:

Originally Posted by EZMachN

Yea, I ran a voltometer(sp?) to the tach output and was getting negative reading.

The Tach output should be an AC signal.

Quote:

Originally Posted by EZMachN

And you can't run the tach to negative coil with MSD b/c it will fry it up and void warranty.

For testing purposes, you can remove the MSD box and then do what Mark suggested.

EZMachN · 07-24-2006, 09:39 PM

Quote:

Originally Posted by Italian LX

The Tach output should be an AC signal.

I'm new to voltmeter stuff. But guy at Auto meter said I should be getting a 1.5 to 5volts from my Tach Output. Would that be -1.5 to -5?

07-23-2006, 07:30 AM	#2
Blown 5.0 Senior Member Join Date: Jan 2006 Location: Looking for more ways to add BOOST Posts: 167	Re: Tach problem Running off the msd you shouldnt need a adapter. I would check ground and be sure i have ground, most of the stuff in and around the dash is plastic, may be nessary to just run a temp. wire from ground and hot battery just for checking purpurse. does the needle move any at all? Does key on and key off make any differnce? May have a bad tach. Hope this helps __________________ Hauling A** on Pump Gas !!!!!

07-23-2006, 11:03 AM	#3
EZMachN Senior Member Join Date: Mar 2005 Posts: 515	Re: Tach problem I have the ground ran through my firewall onto the fenderwell. Once cranked I can turn the needle with the shift set knob, but it won't go past 1k rpms, it stops there

07-23-2006, 11:13 AM	#4
EZMachN Senior Member Join Date: Mar 2005 Posts: 515	Re: Tach problem It is getting power from the key on, b/c once key is on(not cranked) it will move to the previous shift point. Once cranked it drops to 0 then shoots to 5k(shift light point) and sit there. Which makes me think either need adapter or broken tach

07-23-2006, 05:18 PM	#5
Blown 5.0 Senior Member Join Date: Jan 2006 Location: Looking for more ways to add BOOST Posts: 167	Re: Tach problem Broken Tach __________________ Hauling A** on Pump Gas !!!!!

07-24-2006, 05:57 PM	#6
EZMachN Senior Member Join Date: Mar 2005 Posts: 515	Re: Tach problem Bought a $185 Auto Meter Sport Compact today. Still don't work I'm thinking its the damn MSD?

07-22-2006, 09:23 PM	#1
EZMachN Senior Member Join Date: Mar 2005 Posts: 515	Tach problem I installed my Auto Gauge tach tonight. And its not working. The green wire is in the MSD 6al Tach Output slot, Red is in fuse #11(radio), Black grounded, and White into fuse #13 (Illumination). The needle just sits on the shift point and won't move. Does this sound like I need a tach adapter or need to do some rewiring?

07-24-2006, 06:47 PM	#7
04 Mach1 Bet I red light B4U Join Date: Aug 2005 Location: ANNISTON, AL Posts: 975	Re: Tach problem Hook the tach signal wire to the neg side of the coil that way you know you have a signal. The tach output on the msd 6al might be burntup.

07-24-2006, 08:58 PM	#8
EZMachN Senior Member Join Date: Mar 2005 Posts: 515	Re: Tach problem Yea, I ran a voltometer(sp?) to the tach output and was getting negative reading. And you can't run the tach to negative coil with MSD b/c it will fry it up and void warranty.