Tachometer install Help

G-RELL

FULLY DIPPED LS
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Ok, so i picked up two gauges from Depo racing... Gauges look awesome and seem good quality. I went with a voltage gauge and tachometer for my a pillar pods. I went with a tachometer for a couple reasons... Ive searched and havent found too many that have done it before, and those who did didn't explain much...

My directions that came with them say " attach the sensor wire to the Tachometer Signal wire off the ECU"... I've been told 1st gen's might have this wire off the PCM ( Purple/blue)... but was unable to locate it. I took the cabin filter assembly out but could not find a Purple/Blue in any of the three connectors, not saying its not there, just cant find it. it was tough to tell if they were brown or purple...

I've thought I read (cant find it now) that i need to run the signal wire to the pulse wire of the injector off cylinder #1 (thats brown / white)..

as does this
http://alarmsellout.com/support/diagrams/vehicle/LINCOLN LS 2000-2006.pdf

but the12volt says

http://www.the12volt.com/installbay/alarmdetail/1312.html

I tried the brown/white off cylinder #1's injector and got nothing...

NOW.. the signal wire itself had a tag on it saying " connect this wire to the (-) of a coil... anything else would cause damage...


Any ideas guys, If anyone was the location (if it exists) to a tach signal wire off the pcm, or a diagram for it or a pin #?... Also willing to pull cluster to search for a purple/blue wire if someone can confirm...

Thanks to Joe and Marc for their help so far...
 
usually you can get the wiring manual for your yr for like $10-15 on ebay; i would trust it over anything else if you have kept everything pretty stock
 
I'll try to take a look at my manuals to see if there's anything promising. One would hope so, but it depends on how they did the in-dash tach.
On a traditional coil-distributor ignition, the negative side of the coil is pulsed for each spark, which the tach can read and translate to RPM. Not many are made to go to a single COP because that's just not as common. There are adapter boxes that can tie onto a COP signal wire and translate to a tach signal, i.e. MSD 8913

Just out of curiosity, why add an aftermarket tach?
 
awesome thanks... so i'm guessing just tapping in to one of our COP negatives would not pick up the same type of pulse? ... I'll probably try to pull the cluster and see if i can find the tach wire off the cluster harness... (if anyone could confirm color code that would be great). If not there i'll look into the MSD...

No real great reason.. I was looking for something to hold a volt gauge when i found a LSK pod... I'll be starting an alt project soon and think having the RPM's next to it will help monitor after install... Plus i cant see my tach when I drive (i could, but these cars are far to comfortable to move to see) I also couldn't find anything else i liked, and these gauges are awesome...Stupid to some i know...but hey, you have your car to sorry about :D:p:D:p
 
A decent wiring resource...

http://www.autozone.com/autozone/re...epairGuideContent.jsp?pageId=0996b43f802e86d3

I didn't see anything and bet Ford ran the tach signal through the network bus. On diesels I'll run an auxiliary proximity sensor off the crank for a tach.
DSCF0950.jpg



or you can also buy an alternator convertor (although I've never played with one of those)
 
awesome thanks... so i'm guessing just tapping in to one of our COP negatives would not pick up the same type of pulse? ... I'll probably try to pull the cluster and see if i can find the tach wire off the cluster harness... (if anyone could confirm color code that would be great). If not there i'll look into the MSD...

It is a similar pulse, but there's only one per every other rev instead of four per rev (for a v8), and aftermarket tachs just don't accept that kind of a rate.
 
it does have a cylinder "fire" select on the gauge... but im guessing i would need it to be able to read a V16 to work properly???
 
OK, sorry it took so long, finally got the manuals out.

But, it's not good.

Per section 413-01-6 - Instrument Cluster:
"Tachometer Gauge. The crankshaft position sensor is hardwired directly to the PCM. The status of the crankshaft position sensor is sent from the PCM to the instrument cluster via the SCP communication network."

So no easy tap/splice to get a standard tach signal.
Now, if you can find a tach (or an adapter) to run off a crank sensor, then you can splice into the existing sensor (and probably not mess anything up). I don't know how many ticks/rev the flexplate has, though. Note that I don't know much about using crank sensors, so YMMV.
Otherwise, one of the tach generators for distributorless ignitions is required. AutoMeter's version is part number 9117, same basic box (might even be exactly the same!) as the MSD.

To use one of those, Fuse 1.12 in the engine bay feeds the COPs, and the green/black wire is the supply to the COPs. The wiring diagram isn't great, so I'd recommend tracing back from the COP harness to find the common point. Looks like all the COP feed wires are green with different color stripes.
 
Awesome stuff.. looks like i might be buying an adapter soon... Ford's online info said the same about running off the crank to cam to cluster ...
 
.... If i had the required equip i would i a heartbeat... But then again if i get the gauge now...I wont have a choice will I... hmmmm :D
 
I find vacuum gauges to be useful on N/A engines anyway. Granted, that's while I'm tuning a carb, but still.
And then you're prepared for the turbo!
 

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