stock tach not working after MSD install

J

Jmood

New Member

Nov 14, 2002

169

0

0

Arkansaw

Mar 12, 2008

#1

• Mar 12, 2008

• #1

I already posted in the power-adders, with no replys...... I just wired in a MSD boost retard, and the stock tach quit working, is there a way to get the stock tach to work with the boost retard? I think its the green/yellow wire on the coil, can I just splice? thanks.

 

N

noslow1986

New Member

Mar 25, 2006

274

0

0

oswego Il

Mar 12, 2008

#2

• Mar 12, 2008

• #2

i had to get a msd adapter for 86 and it works now. its called a tach adapter. it fix my problem

 

Fast63

New Member

Sep 20, 2007

717

0

0

Mar 12, 2008

#3

• Mar 12, 2008

• #3

When I installed an HEI distributor, I took the intrument cluster out and ran a wire off the back of the tach, straight to the coil. I have since returned to using duraspark for smog reasons, but when I hooked up all the factory wiring, the tach didn't work. So I used that same wire and ran it straight to the stock coil. There should be three "prongs" on the back of the tach, and if I remember right, I hooked the wire up to "the one in the middle"

 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end

15 Year Member

Nov 11, 2003

6,945

1,598

223

Northern KY

Mar 12, 2008

#4

• Mar 12, 2008

• #4

Fast63 said:

When I installed an HEI distributor, I took the intrument cluster out and ran a wire off the back of the tach, straight to the coil. I have since returned to using duraspark for smog reasons, but when I hooked up all the factory wiring, the tach didn't work. So I used that same wire and ran it straight to the stock coil. There should be three "prongs" on the back of the tach, and if I remember right, I hooked the wire up to "the one in the middle"

Click to expand...

That's my problem...i stopped running a Duraspark and now my stock tach doesn't work (no idea why because i don't think the tach runs through the duraspark). I'm planning on making a whole new engine harness for mine since it's carbed and i only need a few wires for the engine.

 

Fast63

New Member

Sep 20, 2007

717

0

0

Mar 13, 2008

#5

• Mar 13, 2008

• #5

I think the tach actually does run through the duraspark, but I don't know for sure. Maybe try the method I described. My tach works fine right now.

 

blckstng96

Member

Apr 13, 2004

208

0

16

Mar 13, 2008

#6

• Mar 13, 2008

• #6

i got this same problem,i think im gunna try and run that single wire from the factory tach like you did.middle wire you say?

 

rd

Founding Member

Jan 12, 2000

3,316

63

109

Ocean Springs MS

Mar 13, 2008

#7

• Mar 13, 2008

• #7

If you are carbed an using a Duraspark, the tach runs off the neg coil terminal. There is a wire from the neg coil terminal to the tach signal input terminal through the harness. The connection from the dash harness to the back of the cluster is a problem on all of mine, and a problem there may be why your extra wire worked so well. You really should not need the added wire.

I have a Jacobs on one car, and needed a tach adapter.

I have an MSD Digital 6 on the 82 Mustang, and it has a tach output connection, which runs the stock tach just fine. It is connected to the original tach feed wire . That was one reason I bought it, having suffered through the Jacobs problems. Only problem now is the connection at the printed circuit board is old so the tach stops when it's cold out!
With the regular 6al, I think the MSD tach adapter is the best bet. Call MSD and ask, as there are several versions of their tach adapters.

 

Fast63

New Member

Sep 20, 2007

717

0

0

Mar 13, 2008

#8

• Mar 13, 2008

• #8

blckstng96 said:

i got this same problem,i think im gunna try and run that single wire from the factory tach like you did.middle wire you say?

Click to expand...

I believe so. There are three threaded studs sticking off the back of the tach. Make a wire with a ring fitting crimped on and then find a small nut that threds on to the stud to fasten it down. Somehow I figured out which one was the right one, I think by seeing where that green wire with the yellow stripe led to. Like RD said there is like a printed circuit board on the back so follow that. I think you'll figure it out.

 

blckstng96

Member

Apr 13, 2004

208

0

16

Mar 14, 2008

#9

• Mar 14, 2008

• #9

wait,so is running the wire to the wire from the middle post of the tach going to work if i have an msd 6al?

 

Fast63

New Member

Sep 20, 2007

717

0

0

Mar 14, 2008

#10

• Mar 14, 2008

• #10

If it runs from the tach directly to the coil, then yes because it is totally independent. But I think even if there is a wire coming off your MSD box for the tach, then it should also work. I just noticed you have a 96 stang though, so I'm not sure what your tach looks like. We were discussing the 85/86 tach.

 

blckstng96

Member

Apr 13, 2004

208

0

16

Mar 14, 2008

#11

• Mar 14, 2008

• #11

Oh,im talking about on my 88lx

 

M

MadRed92GT

Founding Member

Oct 22, 2001

104

0

16

Jackson Tennessee

Mar 14, 2008

#12

• Mar 14, 2008

• #12

Mine just quit the other day for no reason. I've done no work at all.

 

Fast63

New Member

Sep 20, 2007

717

0

0

Mar 14, 2008

#13

• Mar 14, 2008

• #13

blckstng96 said:

Oh,im talking about on my 88lx

Click to expand...

Your 88's tach is still different. Maybe post a pic of the back of your tach?

 

blckstng96

Member

Apr 13, 2004

208

0

16

Mar 15, 2008

#14

• Mar 15, 2008

• #14

ok i'll try and get one.i carbed the car,thats why it doesnt work now.gotta figure out how to wire it up with the msd.i would like to do it without a tach adapter.