No vacuum at front axle actuator

Hello



I just joined the forum.



I am working on a 2010 Tacoma 4X4 with the V6 engine. The problem started out with no 4x4 flashing 4X4 light and a check engine light.



I jacked the truck up and checked the front axle vacuum actuator first. I found that they had run over something and broken the vacuum hose off flush with the actuator case. I started the truck and put a vacuum gauge on the hose and found no vacuum.



Then I put scanner on and found the following codes 0300, 0301, 0303 and 0174.



These indicate a large vacuum leak. Now my problem is I am unfamiliar with this truck. Would someone who is familiar with this truck please advise me as to where on this engine to look for this leak. I have removed the large plastic cover over the plenum and find there is a lot of disassembly required to get to the top of the engine.



Thanks in advance



Phil P

 

http://www.customtacos.com/tech.old...f/06toyrm/06toypdf/06rmsrc/rm2006ta/03700.pdf

http://www.customtacos.com/tech.old.../06toyrm/06toypdf/06rmsrc/rm2006ta/037000.pdf

https://www.tacomaworld.com/threads/how-to-trouble-shoot-4x4-actuator.263525/

Despite even Toyota referring to the front diff actuator (ADD - automatic differential disconnect) as being a vacuum actuator, it is actually electric. The line you found broken off is a vent, thus no vacuum to it.

Welcome to TW.

 

Hi


Thanks


I have the manual marked Courtesy of TOYOTA MOTOR SALES, U.S.A., INC. and it has that electrical diagram also but in the text describing the function it refers to a vacuum line.


Thanks for the information I was wondering about the lack of a vacuum diagram to go with the electrical diagram.


This is why I wanted to communicate with someone with first hand experience.


Thanks again.


Phil P


PS can you tell me how to get this out of the vehicle?

 

Post 7 here has some pictures and shows the common solder fix.

https://www.tacomaworld.com/threads/how-to-trouble-shoot-4x4-actuator.263525/#post-6450282

 

Hi


Thanks for the URL’s to the pictures but all of those appear to be on the back side of the axle. Our unit is on the front of the ale and very close to the front cross member has anyone here removed one like this?


Phil P

 

Hi here are some pictures.
I said I was a heavy equipment guy do you think those jack stands will hold the front of the Tacoma up?




This is the front axle of our 2010 Tacoma. It just doesn’t look like I can get the actuator out.



What do you all think?

Phil P

 

The link spongejosh posted above (https://www.tacomaworld.com/threads/how-to-trouble-shoot-4x4-actuator.263525/#post-6450282) they mentioned having to pull the two front diff mount bolts, to get access to the actuator bolts.

 

Ive got a full array of tools and never remove the diff mounts to get the ADD off.

It's just a breather as others have said.

Your codes are indicative of a dirty MAF and worn out spark plugs. P03## codes are misfires.

I would start by replacing the spark plugs if they haven't been replaced in 50k mi and cleaning the throttle body and mass air flow meter.

 

Thanks for the suggestion you had no way to know the plugs are new.



I agree the 03## are miss fire code but the0170, 0171 and 0172 all together with the random miss fire and 2 misfires on opposite side of the engine indicates a severe vacuum leak.



However now that the question of the vacuum line being a vent line being answered I would now have me looking at the MAF instead.



The records indicate Spark plugs replaced at a major high mileage service only a couple thousand miles ago.



We had 3 of these but one went swimming and they don’t do that well.



Phil P

 

He came to the rite place to get answers .
I will simply throw the book at him

COMPLETE SERVICE MANUAL http://www.customtacos.com/tech.old/...SM/repair.html

 

Thanks for pointing that out. I assume then the dif can be lowered enough so the actuator will clear the cross member without doing any damage. It is so close now that I can’t get my fingers between the plastic cover and the cross member.

Phil P

 

Pull the two front bolts that hold the Diff up and let the Diff hang down. You can then get the actuator out. 30 minute job to get it out and back in.

My actuator failed twice. The thing sucks

 

here are pictures will i be able to get that unit off now?

 

I got it off I dont think there is any repair for this one.

 

Worth giving a shot. Spray it out with brake cleaner, wipe it down, run 12v from your battery to the motor and see if it spins. If so, check the swipe arms that make contact on the contacts on the black cover. Bend them if you have to to make sure they make contact. Wipe the contacts real good to get rid of corrosion. If not, then buy a new one

 

I have a question about the vent hose. I just removed my actuator and the hose is broken clean off where it attaches to the actuator. Is this something to be worried about or is it just the lesser of two evils to prolong the life of my actuator and not have to buy a new one? Thanks!

 

Common problem. This opens a hole to the inside of the actuator to water which will ruin the unit. On my first Taco I removed the cover, got a small brass barb from the home improve store (its a ferrule used for refrig. water lines), cut off the wide end of the barb with a Dremel, drilled a hole through the cover the O.D. of the ferrule, glued the ferrule into the cover just a tiny bit with plastic-specific super glue. Works great.

Note: you should remove the cover before drilling as there is a plastic gear in the A.D.D that can easily be damaged.

 

Hello All

Found a new one still in the Toyota packaging on the Internet. Installed it and replace the vent hose and routed it up high under the hood.

Benn running well ever sense.

Phil P