How to wire up Premium Fuel Switch

In a few weeks, I'll be adding the LA2 computer to my 86 TC, along with the large VAM and ACT sensor (as soon as I get the intercooler in, that is).

In order to deal with PIN 24 on the new EEC, rather than just grounding the pin so it will run in Premium mode all the time, I got the original switch from Wes (Thanks Wes!). My question is: how do I wire this up? There are three wires (Black, Black/White, Red/Yellow).

Also, not to be a dummy, but where does the switch panel go (the one w/ antenna, ride, and fuel switches)? It didn't come with the car, and I'd like to put it in the appropriate place.

Jeff - did I remember you saying (a while back) that you grabbed an ACT sensor off a Taurus intake, or was that TurboMG?

Thanks!

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Phil 86 TC

Originally posted by philS:
intercooler in, that is).


Also, not to be a dummy, but where does the switch panel go (the one w/ antenna, ride, and fuel switches)? It didn't come with the car, and I'd like to put it in the appropriate place.

The switch goes on the right side of the steering colum next to the steering wheel. Don't you have anything there? If you take off the panel you should see where it mounts up. Let me know if you need the panel with the opening in it for the switches. I still have it. It didn't occor to me that your car might not have that opening already there.
Wes


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1987 TC:
Hurst compition plus shifter,K&N cone,rollor cam,custom single exhaust,Gillis valve,H&R springs,KYB shocks,struts and quads.
3.73 rear. lots more to come!
Linton Indiana

Wes

I guess for the pre-87 t-birds, they must have put a blank panel over this. That's what I've got anyway. Now that I think of it, the 86's did have the power antenna option (even though I don't have it), so that switch had to go somewhere. I may take you up on the offer for the trim piece (with the opening), if it looks bad with the hole cut out of the flat panel. I already cut a notch in it to run my boost gauge vac hose, so what's one more hole? [Image: biggrin.gif]

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Phil 86 TC

Phil... as far as I know, all Ford ACT sensors have the same resistance vs temp characteristics, so any ACT from any mid 80s to mid 90s Ford should work. Just remember to grab the electrical connector from the JY along with the sensor. Dont know for sure, but the ACT electrical characteristics may have changed in the mid 90s when OBDII came in to the picture.

As far as the reg/prem switch, in the original application it is wired thru a relay. One switch wire goes to 12V hot in run, one is a ground, and the other is the switched 12V output wire. The ground is used for the little light in the switch that lights up when it is in the premium position. The switched 12V switch lead went to the relay coil, and the relay contacts grounded the prem fuel EEC pin. If you dont mind not having the little "on" light, just use the switch as a 2 wire switch to ground the EEC pin directly.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 00 Windstar (wifes vehicle)

Jeff: Thanks for the info. I'll let you know how it turns out once I wire it up.

Wes: Since I've got an extra slot on the headlight switch panel (no headlight auto-dimmer, but cooling fan switch in one of the slots), I figure I'll put it there.

Jeff,

I hate to bring up the oldest thread from the dead, but I know you know your s#!+.....

I’m trying to wire a premium fuel switch in my 86’.

I have a pimp setup, and the fuel switch table is ground switching...

I’d like to try and make the light work on the switch, but I’m having a hard time designing the circuit. And I don’t wanna feed the pcm 12v.

^^^^ Sorry it took me so long to respond. I didnt see your post until just now.

I assume by ground switching you mean when a particular pin on the PIMP needs to be grounded for the premium fuel table. If that is correct, The same advise I gave Phil years ago still holds. Key on power to one switch terminal. Ground the light pin on the switch. The switched 12 V pin on the switch goes to one of the coil terminals on a small 12 volt relay (no need to use a 30 Amp relay or anything like that). Other relay coil terminal goes to ground. One of the NO (normally open) relay terminals goes to ground, and the other relay terminal goes to the PIMP.