Hi everybody, This is my first post on this forum... I just read a few threads , seems like a good forum

Okay, of course I have a question for you!!

I bought the truck without a tach, thinking no problem, I'll ad one......

not as easy as I thought.

It's a '02 f150 xl 5 speed, 4.2,

It has a distributorless ignition which means no negative coil side to hook a tach, been trying to figure out how to wire the thing. Found a ref that said use a red/grn wire on another site. I tried it and it sits at about 650 rpm, but only goes to maybe 1500 when i rev it, it aint working right

Anybody done this before ? got it working ?

Thanks,

Mike

02 f150 4.2

 

You might want to look at a Hayne's or Chilton's manual for a wiring diagram. My 01, 4.2 5-speed has a factory tach in the instrument cluster so there has to be a connection or splice point somewhere in the harness.

 

connect your tach signal wire to "PIN 48" on your ECU located directly behind the batter. Just splice it. It'll work perfectly.

Talley
4.2 Guru

 

hey, thanks for the tip i'll try that tomorrow

i've been using the trip button test method, i've been short shifting by about 2k rpm, defiinite kick in the "little motor that could" above 3500rpm

Mike,

 

Not sure about your '00 but my '97 offered an easier location to connect tach wire than on ECU under the hood.Look in forum on '97 - '03 F-150 and E-150.Info is there.

 

Well, short version still not working...

Long Version...

I pulled the battery, the tray, some little reservoir of some kind attached to the battery tray in order to get to the connector....

There is no wire in location 48 on the connector we got a 47 and a 49.... but no 48, wah...

I happen to have an old SunPro multi-function meter that has a tach function, so I grounded that and started prodding wires in the harness to see if I could find the tach signal.... no luck...

hhhmmmm, well if the dash gage cluster is displaying a tach in the test mode, it must have the signal there....

about an hour later..... had the gage cluster splayed in front of me, tested every wire going into the cluster, no tach signal.... at least none that my meter could read anyway....


I give up. At this point I know how to remove the gage cluster, so gonna check out getting a cluster with tach from a bone yard

I'll try to swap the odo if I go down this path.... I've bought and tried to hook up this stupid tach 3 times... each time I end up taking it back... this is strike 3.

Unless of course one of 'yuse guys knows what I did wrong...


Mike
02 f150 4.2 (tachless....)

 

NO NO NO!!! Go under the dash to the wiring harness and very carefully cut tape surrounding wires,seperate the wires enough to locate a WHITE wire with a PINK stripe,remove a small amount of the insulation on this wire and install your tach wire and wahla you have and operational tach.

 

guys, not sure what stripping my wiring harness is gonna do for me, if i prodded all the wires going to the cluster and none have a readable tach signal .... there is a tach signal getting to the cluster because the test mode works... my sunpro tach and the sunpro diagnostic meter i have can not read the tach signal...

I think it was somebody here who mentioned in another section that ford has sorta acknowledged this problem and ford motorsport just posted on may 23rd of 2002 a device to convert the signal from a distriutorless ignition tach signal to something an aftermarket tach vendor can read. $55.00

http://www.fordracing.com/news/?article=19236

check it out...

Thanks,

Mike

 

Nimroder-

Not sure it is a good idea to probe every wire with your meter to look for the tac signal. You could now have a busted portable meter, or at the very least a busted tac function on your meter. I could be wrong. Test it on another car that you know it should be working and see if you still get a signal.

 

BRDT I had an old analog meter that i fried twice because the rotary know had a thin line on side, i kept
putting 180 degree's from what i thought it was and blowing it up. I went and bought the SunPro digital meter, this guy is fused so it's tough to blow it up

I may be ordering the tach converter in a few weeks, once i get back from bike week...

Mike,
02 f150 4.2

 

Nimroder,

I bought a tach too, same type idea as a sunpro. You say we have to hook up the tach signal wire to a "white pink striped wire". Well i has my dash in peices and the only wire like taht was leading to teh clutch mechanism. Is this the right one???? If not where is it exactly, i need a specification of its whereabouts, cuz tehre is like a million differentthings taht look like wiring harnesses!
Thanks!

 

Has anyone installed a tach using pin 48 on an F150 4.2L V6 2003 model year? I just installed using the instructions, and tachometer lights function, but no RPM reading. Any other place that I can get a signal for the tachometer?

 

Yea man, Been running a Sunpro Super Tach II for years, works like a charm.
It's the 2 1/2", mounted just right of center on the steering column.
The pin 48 location is right, and it works.
What I did was take the head of the connector on the firewall loose, take a tiny drill bit and drill a hole
thru the plastic where the wire "isn't".
I then took the wire I installed across the top of the firewall for the tach and soldered a "pin", poked it into the newly drilled hole,
sealed it with some silicone and voila, never failed yet tach.
The only trouble I've had is with LEDs burning out, but the second go round I installed bullit connectors in the wire harness for
the tach and hide them under the little boot flap on top of the column under the cluster.
Hope that helps you fellas.
Yea it took 3 or 4 tries to get the pin "just right" but with some patience it's doable.
Crap, edit, Mine is a 2002 F150 XL Sport 4.2L 5 speed, original without a tach.
Crap, 2nd edit, You want the hole you drill to be a hair smaller than the insulation on the wire you use, once you get the wire into
the hole it helps seal out any moisture.