07 Sequoia 4wd issues

Bought this thing after a buddy looked at it and said it was good to go, he was poorly mistaken.
Some background: I noticed that when shifting into 4wd, it would take forever to actually shift into 4wd. Not too big of a deal but annoying. Our driveway is short and steep to our main road. When I put it in 4wd and try to accelerate up the hill, it cuts power and flashes the VSC, traction and ABS lights and cuts power. I have to just hold the pedal to the floor and eventually it comes out of limp mode and will go (but still cuts in and out of limp mode). It only does this in 4wd. I replaced all the wheel speed sensors as 3 were throwing codes. It still does it. I can unplug the abs harness from the brake cylinder and it will not have this issue. Any ideas? I am thinking I need to pull the transfer case and actuator to clean it out as I am sure its nasty and thats part of my issue with the slow to engage 4wd but what would be causing it to go into limp mode only in 4wd? No issues with power or limp in 2wd ever.

Thank you. Would love to make this safe for my wife to drive again this winter.

 

Forgot to mention the lights only come on and flash when trying to accelerate in 4wd and they do not stay on.

 

Have you followed the 4WD instructions under the driver visor?

Are TC & front diff fluids fresh? Makes a big difference. Mine was like yours when first bought used 12 yrs ago (was 10 yrs old then).

I recommend engaging it well before getting to when needed and if possible just after attempting to engage turn the steering right or left just a bit - seems to help mine when I first got it. As I did this more and more often it began to work more smoothly and on demand - now it can engage & disengage just standing still. But at first it needed movement (forward or reverse AND for the wheels to turn left right as it was attempting to engage to help it get its act together) - this is what worked for me without any repairs (well fresh fluid).

Most likely the PO did no use 4wd much otherwise it would work smoothly now- the more its used the better they behave. Luck.

 

Thanks I will check fluids. I am very aware of how to use 4wd in Toyota vehicles, this is the first one I have had this problem with. I am planning on pulling the shift actuator to see if it is making good contact and will go from there with that issue.

The bigger issue is the activation of the VSC when I am trying to accelerate. I am guessing the computer thinks a wheel is slipping and cutting power but that is not the case and why I did already replace all the wheel speed sensors (used OEM).

 

Pulled codes again this afternoon, looks like my left rear wheel speed sensor is still throwing a code. Gonna have to pull the tone ring and see if it has an issue. Any thoughts? Code were VSC Trac 43/C1223 and ABS 34/C0215.

 

Very interesting. Any updates?

 

Not yet, hopefully have time this week to look at it.