Missing vacuum line

[etc.]

I noticed a missing vacuum line when trying to find the reason my 4wd hasnt been working on my 97 limited.

The hoses that go to the actuators look good.

Where the main small hose comes up for the solenoids, it splits three-ways. At this place I have a missing hose...

FYI both solenoids have a line...

It should be noted, I searched and searched the engine compartment for a hose and came up empty handed.

 

[TheDurk]

That splitter should go FOUR places: two VSV's, plus one to the canister inside the fender and one through the check valve to the manifold. I'm guessing the canister connection is your problem. That line goes in under the main fuse box, then takes a right turn at the fender wall towards the battery, and the dives through the wall at about the battery midpoint at the bottom. There should also be TWO lines coming up from the diff that go straight to the VSV's.

 

[etc.]

That splitter should go FOUR places: two VSV's, plus one to the canister inside the fender and one through the check valve to the manifold. I'm guessing the canister connection is your problem. That line goes in under the main fuse box, then takes a right turn at the fender wall towards the battery, and the dives through the wall at about the battery midpoint at the bottom. There should also be TWO lines coming up from the diff that go straight to the VSV's.

THANK YOU! I've been reading a lot of threads the past couple days trying to get my 4wd working properly. I noticed that your name keeps popping up with helpful hints.

Question. why would my vacuum line go toward the battery when the canister is located at the firewall and fender?

 

[TheDurk]

THANK YOU! I've been reading a lot of threads the past couple days trying to get my 4wd working properly. I noticed that your name keeps popping up with helpful hints.

Question. why would my vacuum line go toward the battery when the canister is located at the firewall and fender?

Those are the VSV's (on fender, not firewall.)The vacuum canister is INSIDE the fender between the wheel well and the headlight, accessed through the wheel well--plastic cover at top front. It provides reserve power to cycle the actuator when engine vacuum alone is not sufficient--which is most of the time, that's why you need a canister. Don't confuse vacuum canister with charcoal canister, which is a whole different thingy, although it also has VSV's. THAT is on fender near firewall, at least on '99's. Not sure about '97--it got moved--but it has nothing to do with ADD.

 

[etc.]

Thanks again. When I said firewall and fender, I meant near the corner (like cross streets). However, I got thrown off when I looked on ebay for a replacement...

toyota 4runner limited vacuum canister v6 4x4 : eBay Motors (item 150499981348 end time Oct-28-10 18:43:11 PDT)

As it stands now, I dont have one. I will be on the look out and will call the yards tomorrow to see what they have in stock.

 

[TheDurk]

Thanks again. When I said firewall and fender, I meant near the corner (like cross streets). However, I got thrown off when I looked on ebay for a replacement...

toyota 4runner limited vacuum canister v6 4x4 : eBay Motors (item 150499981348 end time Oct-28-10 18:43:11 PDT)

As it stands now, I dont have one. I will be on the look out and will call the yards tomorrow to see what they have in stock.

WHOA!!!!!! That ain't it!!! That's a charcoal canister. What I am talking about is Part # 41541-35040, officially called Differential Vacuum Tank by Toyota, available here:41541-35040 - OEM Toyota TANK, DIFFERENTIAL V As a new one is $92 on-line, I'd look REALLY good for it. Unless you take that cover off inside the wheel well and look up from under the wheel well, it is INVISIBLE! You just can't see it from looking under the hood.

Here's a diagram:

See the thingy labeled '41541'? THAT's what it looks like.

 

[etc.]

What is this ? a breather?

Is there anything else I may need to go along with this?

 

[TheDurk]

OKAY!! Hehe. It's really gone. I apologize for ever doubting you.

What is this ? a breather?

Yeah, that looks like the actuator breather 41110R in the diagram. That's to keep the actuator from sucking in H2O if some dumb-bunny wants to go into 4WD AFTER they're in the river.

Is there anything else I may need to go along with this?

I can't really tell. Follow the diagram, it's all needed.

 

[etc.]

I got the vacuum canister mounted

Buuut....

The 4wd light doesnt flash. It just stays on.
Front propeller rotates when driving.
4wd engages instantly.
4wd doesnt disengage, unless vehicle is turned off. Then light goes out.

 

[TheDurk]

I got the vacuum canister mounted

Buuut....

The 4wd light doesnt flash. It just stays on.
Front propeller rotates when driving.
4wd engages instantly.
4wd doesnt disengage, unless vehicle is turned off. Then light goes out.

First thing is to see if vacuum is switching from side to side at the VSV's. The answer will tell us which direction the problem is in. Try this: Label the two long hoses so you know where they are supposed to go. With the car in 4WD, pull each hose off the VSV in turn and see which VSV has vacuum. Then do the same thing in 2WD and see if the vacuum is on the other side. If it did NOT change, reverse the hoses and see if it goes back into 2WD.

Post back with the results and I'll tell you where to look next.

 

[etc.]

I forgot to mention:

After A LOT of reading about the issue, I ordered a replacement front diff sensor (part# 84222-35070 ) I should have it tomorrow

I didnt have enough time to test it. Considering a lot of people have them fail, I wanted to replace it just to replace it.

 

[etc.]

First thing is to see if vacuum is switching from side to side at the VSV's. The answer will tell us which direction the problem is in. Try this: Label the two long hoses so you know where they are supposed to go. With the car in 4WD, pull each hose off the VSV in turn and see which VSV has vacuum. Then do the same thing in 2WD and see if the vacuum is on the other side. If it did NOT change, reverse the hoses and see if it goes back into 2WD.

Post back with the results and I'll tell you where to look next.

Will do

 

[TheDurk]

I forgot to mention:

After A LOT of reading about the issue, I ordered a replacement front diff sensor (part# 84222-35070 ) I should have it tomorrow

I didnt have enough time to test it. Considering a lot of people have them fail, I wanted to replace it just to replace it.

Just be aware, all that switch does is turn on the light. It reports, it doesn't CAUSE anything to happen. So if you are really stuck in 4WD, (you can't turn prop shaft by hand in 2WD), then that won't fix it--the light is supposed to be on. If you can turn the prop by hand, and the light is on, then the switch, or its wiring, IS the problem. The switches on the TC are different, they CAUSE the ADD to engage.

I prefer to troubleshoot and find the cause, throwing parts at a problem often makes things worse.

 

[etc.]

First thing is to see if vacuum is switching from side to side at the VSV's. The answer will tell us which direction the problem is in. Try this: Label the two long hoses so you know where they are supposed to go. With the car in 4WD, pull each hose off the VSV in turn and see which VSV has vacuum. Then do the same thing in 2WD and see if the vacuum is on the other side. If it did NOT change, reverse the hoses and see if it goes back into 2WD.

Post back with the results and I'll tell you where to look next.

So I got a chance to try what you said.

I honestly couldnt feel any vacuum off either. The blue soleniod would hiss anytime a line was removed. The red...not. In 2wd, I hit the button and it instantly went into 4wd and the green light stayed on. After it was engage, I drove around for a couple minutes, reversing, forward, etc to no success. I switched the lower hoses and it disengages and the light goes out. Thinking it was a fluke, I tried it several other times and it did the exact same.

 

[TheDurk]

So I got a chance to try what you said.

I honestly couldnt feel any vacuum off either. The blue soleniod would hiss anytime a line was removed. The red...not. In 2wd, I hit the button and it instantly went into 4wd and the green light stayed on. After it was engage, I drove around for a couple minutes, reversing, forward, etc to no success. I switched the lower hoses and it disengages and the light goes out. Thinking it was a fluke, I tried it several other times and it did the exact same.

The good news is your front diff is working fine. Bad news is you wasted your money on that switch--it's working fine, too. Your problem is between the TC and the VSV's. First thing is check the wires on the switches to the TC (there may be two or three of them). They are pretty tough to get to. The wires do tend to break off-road. If it's not the wiring, then it's one of the switches themselves. So think about how to get them out--won't be easy.

The reason things aren't working is the electric signal is not switching from the blue to the red VSV. You can confirm this with a test light/DMM on the plugs to the VSV's--but it's clear this is the case.

In the meantime, you can use 4WD and 2WD just by switching the hoses whenever you switch the TC.

BTW, what happens in 4L?? Actually, this is important. Also, does it re-engage the diff if you switch the hose back to its original location when you have put it in 2H and disengaged the diff by switching hoses?

 

[etc.]

The good news is your front diff is working fine. Bad news is you wasted your money on that switch--it's working fine, too.

Your problem is between the TC and the VSV's. First thing is check the wires on the switches to the TC (there may be two or three of them). They are pretty tough to get to. The wires do tend to break off-road. If it's not the wiring, then it's one of the switches themselves. So think about how to get them out--won't be easy.

The reason things aren't working is the electric signal is not switching from the blue to the red VSV. You can confirm this with a test light/DMM on the plugs to the VSV's--but it's clear this is the case.

I wouldnt say I wasted money. They fail pretty frequently from my reading on the boards. If it wasnt the problem, no biggie. I just wanted to replace it to replace it

I crawled under there today after doing my external trans cooler. I checked the wiring and it appears to be ok. I found some pig tails on the DS near the top of the TC. Do you happen to have a pic? I can search for it, but if you have one that would be great.

Now what to do when I have the TC switches out?

BTW, what happens in 4L?? Actually, this is important. Also, does it re-engage the diff if you switch the hose back to its original location when you have put it in 2H and disengaged the diff by switching hoses?

I havent put it in 4L in awhile. When I did, the green light would come on and engage instantly. When I took it out of 4L and into 4H, it would work as it should.

When I switched the hoses, yes it would switch back to 4wd. It took turning off the vehicle to stop so I could put the hoses in there correct location.

 

[Blitzkrieg]

THANK YOU! I've been reading a lot of threads the past couple days trying to get my 4wd working properly. I noticed that your name keeps popping up with helpful hints.

Yeah, The Durk is a good guy even if he is from Jersey. :uzi:

Just kidding Durk, I've got nothing against Jersey.

 

[TheDurk]

Yeah, The Durk is a good guy even if he is from Jersey. :uzi:

Just kidding Durk, I've got nothing against Jersey.

Hey, I have things against Jersey--but there are some beautiful parts.

Back to work. Etc. We have now isolated the problem to the TC or transmission control. The ADD is fine, it just doesn't know when to operate. I don't have an auto, so I'm just going by my '99 FSM, but your system is the J-handle with the button, right?

So to use the diagnostic I need a Yes/No on each of these transitions:

(I'd tell you to look it up yourself, but the 2002 system in the on-line manual is quite different); no J-handle. My FSM is paper, and my scanner takes sheets only.

H2>H4
H2>L4
H4>L4
H4>H2
L4>H2
L4>H4

I tried laying it out from your posts but it was giving me a headache as I wasn't always sure what you were doing. So give me six Yes/No's and I'll post back the relevant causes per the FSM--some we have already eliminated. Make sure your 4WD fuse is good, that's at the top of half the lists.

Sorry, I have neither pic nor diagram I can post on-line, but the switches should be near the top.

EDIT: I found one http://docs.google.com/viewer?a=v&q=cache:ump1idSs68oJ:www.fjcruiserforums.com/forums/attachments/misc-technical-discussion/29246d1235008447-rattling-noise-transfer-case-02000510.pdf+Vf2a&hl=en&gl=us&pid=bl&srcid=ADGEESiULQN9GReSiqW9bAILKrHP7uEYJEof6drGz1zjVh8WSVjNeVtr9p_usVHf77JCmZgeaAOI_3gZf61YHKbPBt7KC6AzJhGUfiVJbsCOOHBJOPOrKx4a0NaYUnfogOuLdNsn6_oz&sig=AHIEtbTrdl1ZhI9AY3O37Z06fmx6_pPwHg

My upfront guess is the problem is No.3, the 4WD position switch.

 

[etc.]

Thanks for the FSM sheets. For some odd reason, I cant look at the FSM that are online...internet quits working.

Anyhow, thank you for your help so far. I will check in the morning or when the GF goes to sleep.

Oh, and I have the 2H-N-4H + 4wd button.

 

[etc.]

H2>H4 Yes

H2>L4 Yes

H4>L4 Yes

H4>H2 No

L4>H2 No

L4>H4 Yes