Where can I pick up a signal to run a tach and what type of tach can be ran.

Auto meter said to run a single cylinder tach on one of the coils but the multispark at low rpms will make the tach jump until rpm are up into the 3000 range

Can the crank position sensor be used somehow to trigger the tach, it puts out 0.1 volts (A/C)which varies with rpm and also drops every time the missing tooth comes around

 

If you go into the "other aftermarket" section, there are several installation guides in there.

I just put one in last weekend and it was easy. There is a signal wire in the 16-pin wire harness (large middle one) found when you take out the instrument panel (very easy to do). It is the White wire with Pink striping. Just tap into that wire and you will have your signal.

Oh, and I used a Sunpro from Autozone. I know I should have gone with a better one but I bought it about 8 months ago and just never got around to installing it. I thought it was difficult.

Hope that helps.

 

on the back of the tach what is the tach set to run on
1 cylinder or 6

 

I think on some 99's and up that didnt come with the tach in the the instrument cluster (hence that is why i assume your hooking up a tach) that wire wont work. Then some one found the pin number coming out of the computer and if you didnt have a tach in the truck then ford never put a pin in the computer. Hooking it up to the coil wont work cause it will give you a very erratic reading. The only way i know how to do it on newer trucks is to use an Aftermarket ignition box and hook one up off that. But i hope you find a way to do it, good luck.

 

Longhorn ,wondering what year your truck is and if you had a tach in dash to begin with

 

I believe that the Pin in the main PCM harness is #48.

I remember reading a How To of F150World with some detailed instructions on how to install a tach.

Good Luck,
David

 

V6runner,

Sorry, this is Longhorn Hoss (just couldn't find my password so I had to use my other login name).

To answer your questions, my truck is a 97 XL F150, 4.2 V6 4x4. I did not have the tach in the truck when I got it, really strange because it is a standard (I've been made fun of before for it).

I found a post from around June of 99 in the aftermarket mods section that led me to remove the instrument panel. Also, many of my friends have told me that the way most car companies work, they usually use a generic wiring harness for all vehicles, then just place the correct instrument panel based on customer needs. Mine had the tach wire in the back, along with a bunch of other wires I didn't care to research into what they were.

Oh, set the switch in the back to 6 (mine has 4,6,and 8). I will say that I had heard that the correct wire, and this was from another post, was the white with pink striping. Just to make sure, I hooked up the power to the tach, then took the signal wire and tapped it to the back of the wiring harness. Revs showed up perfectly.

One last thing! Make sure that you connect the BLACK ground wire to a ground and the GREEN wire to the tach. I was in a hurry, and mistook the GREEN for GROUND! I had the engine running and while I was tapping the different connectors in the back of the harness, one happened to spark, and kill the engine. DOH! Nothing else happened, she started right up, and ran fine, just a little scare.

By the way, what year is your truck?

 

With all the different information given, and looking through some tech books, I understand that the pin number is 48 which is wht/pnk. It can be tapped into from any point along the way from the PCM to the back of the instrument cluster. The model year does not matter 97-00 , can be used with or with out original tach installed, have not checked it for 01. The tach signal fires three signals per rpm for the three coils, which is correct for a 6cyl. tach. The tach must be self powered and not run off tach signal power only, which some old technology tachs use.
My problem remains to be, that bad ink or a color blind engineer was used in making my wht/pnk wire and the pink appears to very dark, near red. The only wht/red wire I can find is used only on the 5.4 V8 for the ignition coils and is not near the intrument cluster. So I assume that I have the right wire.

My assumptions are unproven until I hook up the tach, that I am currently looking for, and all goes well.

My application is a 00 with no original tach

 

The reason I went with the instrument cluster is because I did not have a wiring diagram of the vehicle so it was kind of difficult to find the wht/pnk wire. That kind of sucks that the coloring is not quite what it should be. I hope all goes well with the installation. Have you considered which tach you will install?

Oh, V6runner, how much did it cost to swap your gears?

 

Im looking at one of the auto meter tachs.
5 in. 8,000 rpm external shift-lite either in the sport comp or auto gage model but I see no visible difference in the two only the white printed name and the price.

The gears themselves are $150
Install kit seals, shims, shim holders, bearing, ring bolts, crush sleave are $70
Extra crush sleave from ford $8, one backup so I don't have to wait for another if the pinion drag is too much and have to start over

Also noticed that factory pinion seal leaked and rusted pinion to pinion bearing inside diff were oil should be and water should not,
made the job alot more fun breaking it loose.

 

V6, Who did you get your gears from?

 

I got them from a local place. When you shop notice where the place is since shipping heavy gears will bump up the price. Off road magazines are loaded with plenty of places, and prices that you can search if no one is local.

 

No tach on a standard? Nothing new. Manufacturers will do anything to save a buck nowadays..

 

i think on the 2001's wiht the digital odo, you cant hook up a tach to the dash harness. i found a wire that had a tach signal, but when i hooked up my tach the signal was all choppy and bad; with the engine idleing smoothly the tach jumped around between 500 and 1000 rpm. when i use the odometer tach, it works fine, but this is annoying since its digital and since it resets the trip odo everytime i use it.

if anyone knows how to get around this without messing with the computer, please let me know. i really dont want to destroy my $800 computer by soildering on it. thanks.