Tach signal help.
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Joined: Apr 2008
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Tach signal help. Not really sure where to post this but here goes. I've got an '03 5.3 DBW engine in my malibu and hooked up a NOS window switch today and I'm not getting a Tach signal from the white wire that I believe is the tach signal. I have continuity from the Switch to the white wire. is there a test I can perform to check for signal on the white wire or do I have the wrong wire marked as tach? Are the DIS systems batch fire or sequencial? I can just tap into a coil trigger wire too.
Joined: Sep 2004
Posts: 3,148
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From: Downers Grove, IL
The DIS system is sequential. If you are tapped into the tach wire it is a 4 cylinder signal (unless that was changed when your PCM was tuned) and it is a 5V signal instead of 12V so your window switch may accept it, or you may have to build a pull up circuit.
Here's the description for a tach 'boost' ckt, courtesy of "FastKat"-Dave.
I used it successfully. It's very easy.
Scroll down toward the bottom of Dave's build. There'll be details & photo.
http://www.buyrcars.com/jag.htm
I used it successfully. It's very easy.
Scroll down toward the bottom of Dave's build. There'll be details & photo.
http://www.buyrcars.com/jag.htm
Thanks! To be fair, I stole the pic from LT1swap.com - it's in my September 12, 2010 entry, about 3/4 down the page. Make sure the power wire has a fuse on it!
Here's the description for a tach 'boost' ckt, courtesy of "FastKat"-Dave.
I used it successfully. It's very easy.
Scroll down toward the bottom of Dave's build. There'll be details & photo.
http://www.buyrcars.com/jag.htm
I used it successfully. It's very easy.
Scroll down toward the bottom of Dave's build. There'll be details & photo.
http://www.buyrcars.com/jag.htm
