the relay is by the brake pedal area, i only found it cause mine was clicking back and forth but i wasnt getting 4wd. just to see put it in 4wd and then apply 12 volts to the blue side i think is the 4wd side and see if the light comes on.

 

do you remember which one? there is 5-6 down there lol

 

mine is right next to the ebrake bar, on a tab and it looks just like the fuel pump relay, i switched mine before and now have the fuel pump relay in its spot.

 

The fuel pump relay is right there next to the ebrake handle. is there another spot right over there that maybe im just not seeing it?

 

that is the relay for the add... look at the link, see if when its running put ur finger on it and see if its clicking



http://www.ncttora.com/fsm/1990-1995...c/relayloc.pdf

 

well I stuck my head under there. If i turn the ignition to on that relay does not click. it also does not do anything if i shift into 4h. so ill go take it out tomorrow and test to see what i get.

That diagram doesnt exactly match what im seeing. This relay that is marked fuel pump is a rather large relay in physical size. does that sounds about right?

 

yeah its a larger size relay, what u could do is just pull that one and the fuel pump one and switch them, if it wont start or run fuel that one is bad,

 

im just gonna bench test it. ive got PSU's laying around. good idea tho.

 

how do you get that freaking relay to come out??? ive bent, twisted pulled, everything short of breaking it trying to get it off....

 

So the ADD relay doesny have power at all. From the schematics im assuming the 2wd valve has power at all times. well according to my testing that is not the case. Bad wire? am i missing something like a fuse somewhere?

 

black orange should be the power wire. and it says there is a 10 amp fuse. and from what i was looking at the gauge fuse powers the add system

 

yeah i agree on the 10a gauge cluster fuse...its all good on that side. looks like im gonna make my own wire to it.

 

i would run a test wire from battery and see what happens before u try and do all the work and it not still work out like it should.

 

thats the plan

 

Looks like the relay is bad. seems like an odd part to go out.

Heres what i know so far.

Xfer case switch works as its supposed to
Both valves actuate and vacuum flows through both
There is power getting to the relay, i ran my own power to it
The grounds on the wires at the relay match up to the ground on the valves
Relay does not click at all either way going into 4wd or 2wd and i cant get it off the truck so i can bench test it ( cant see enough to figure out what is holding it on).

Im through process of elimination, that leaves the relay. anything else i may be missing?

 

it is a pain in the butt relay to get off, i dont remember how i got mine out but i have had it out and had a hell of a fight but if u know its bad then if u brake it getting it out and not destroying the wires. but it looks like u have gone threw everything else to eliminate items that are still good vs bad... but i think u found the problem just need to get it out and replace it.

 

I'm having problems with my ADD system as well. This is the second time in six months.

Is there a downside from eliminating it outright?

http://www.4x4wire.com/toyota/tech/add/


Will this effect fuel economy? Will it make things up front more prone to wear?

 

Do that and swap out the front drive flanges for manual locking hubs and you'll have a good setup. Hubs unlocked and you'll have less wear and tear than now and it'll be more reliable to boot.

 

Fortunately for me when I bought the truck I had to drive it from Vancouver to Yellowknife and had a lot of work done to make it safe and reliable. One of those things included manual hubs!

I had it in 4 wheel drive for the past few weeks then took it out leaving the hubs locked. Two days later I could not get it back into 4x4 mode. I'm wondering if it's the cold?

Anyway, this is the second time in six months I've had to get into it. First time a shop did the repair because I'm very new at all this never having worked on a vehicle before.

The instructions seem pretty straight forward and I happen to have diff oil in the garage as I was planning to change out both diff oils for the cold climate. Probably have water in there from the summer and having it freeze and expand could be bad......


Anyway, the clamp. Is it just a metal hose clamp I can get from the hardware store?

What do I cap the hoses with? I'll head out to the shop once I know.


Really appreciate your help!

 

Article says "hose clamp or CV boot clamp", that would be as you surmise.

You can buy vacuum caps at the auto parts store, I picked up an assortment years ago, they just slide onto the ends of the hose barbs (red caps in the photo below):


Or you could just shove a golf tee or screw into the end of the disconnected vacuum lines and tape it in place.