wholiman

Hey... Sorry if this has been posted already...New to the whole forum world. I have a 94 4runner sr5. it has the 3.0 v6 and an auto trans...It seems as though the 4wd is quiting anytime my truck is wet. living in northern oregon in winter doesnt allow it to dry out very oftern. now i know i have a bad seal around my windshield, because water is constantly dripping inside...thats what i've noticed... let me run you through what happens....


When i shift it into 4wd i get the electrical clicking in the dash, and sometimes it even feel as tho it clicks in...but no idiot light on the dash... and absolutely not in 4wd

Other times when i shift into 4wd i get the electrical clicking in the dash, feels like it goes in... and the bright green idoit light.... and then it is in 4wd.


I dont know guys HELP ME PLEASE

91_4x4runner

I have the same issue but its only really affected on wether the vehicle is at operating temp or not for me... Sound familiar?

91Toyota4x4

Is it ADD? If it is I bet that's broke.

91_4x4runner

If it's ADD, it is possible that the vacuum isnt working correctly... I haven't really looked much into the system myself but there is someone who posted a writeup on "defeating the add system".

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

There is a link that may help you get started if you go looking into it.

wholiman

It seems like it doesnt really matter for mine...I will check into the ADD thing... add...attention defecit disorder... yeah that pretty much describes my yota....

Thanks for the link

Memphis4X4

I had an issue with my 4WD system on my 4-Runner and was able to trouble shoot and fix it. You should be able to do the same too.

The ADD is actually pretty simple. There are a couple of relays hanging on the inside of the passenger fender in the engine compartment. You will see a bunch of small vacuum hoses running to these as well as two of these same hoses then running down the inside of the wheel well to the front differential. When you shift the lever in the passenger cabin into 4WD, the relays switch and vacuum actuates the front diff. Your problem is somewhere in the vacuum system.

First, with the engine running and the truck in park (emergency brake pulled for safety) pull one of the small vacuum hoses off of the inlet to each of the relays.....you should hear the sucking sound and feel the vacuum pull when you use your finger to seal the open end of the hose. Next pull the front skid plate off from below the front bumper and the front suspension brace assembly to expose the front diff. You will see the two small vacuum hoses that run from the relays in the engine compartment attach to two nipple fitting s on the diff. With the truck running and e-brake pulled and the 4WD lever pulled, pull these two small hoses off the nipples and see if you can feel vacuum from them. If you do, then the problem is in the mechanicals inside the diff. If you don't, then the problem is in the hoses running down to the diff. That is where the problem was with my ADD......the two small vacuum hoses running from the relays had cracked with age & heat cylces of being so close to the exhaust headers that they started leaking.

Another area to look at there is a vacuum collection canister behind the front bumper in the passenger wheel wheel. Check those hoses to make sure they are not leaking.

I'm trying to think of a reason why rain (wet) would make you system not work wholiman....unless the water is somehow affecting how much vacuum your truck pulls.

Any ways, I hope this helps you solve your problem.