4.0 codes- vtti related?

So I was out running an errand on my lunch break yesterday, and I pulled over to adjust the strapping on some lumber that had shifted.

I get back in the truck and wait for traffic, go to pull out and the rear wheels slip (dirt driveways out here) and I wind up waiting for more traffic to pass by.
While the wheels did slip, I thought the engine hesitated a bit and it didn't feel right.

I get moving and maybe a hundred feet down the road the engine bogs down like its ignoring my throttle input- "%#@#^ computers!" I thought. I HATE this drive by wire nonsense. The engine is ignoring my throttle input and the truck is slowing down... 30mph, 28.... 25... meanwhile a logging truck is coming up behind me going probably 50, noticing that I just pulled out in front of it just to slow down. GREAT.

I pull over and wait for more traffic to pass by, and notice the CEL and TRAC lights are on, which I read it was common for them to come on together so I wasn't too worried about the pair.

Truck is clearly in "limp mode" - I get get it up to 30mph or so, but then it just slows itself back down to about 20, or starts shaking violently.

I'm used to my '99 which never gives me problems, so when I finally limp it home (about two miles) my scan tool is nowhere to be found... take the '99 out and buy yet another cheap one.


p0016 Crankshaft position camshaft position correlation bank 1 sensor a
p0012 Camshaft position timing over-retarded bank 1
p0011 camshaft position timing over-advanced or system performance bank 1
p0300 random/multiple misfire
p0011 camshaft position timing over-advanced or system performance bank 1

I write those down and call it a night.
Today I went out and scanned it again, and the p0016 is conspicuously missing.

Looking up the other codes on this site, a lot of people say the VTTI solenoid is a common issue on this truck, as is the "screen" that filters the oil going into it.
I did a quick youtube search on where I can find these two things and I see a few videos showing it's right behind the alt- they make it look so easy!
I went outside to check mine before work today and there's NO way I'm getting in there without removing the oil filter mount and the alt, and maybe the battery....

Before I go digging, can anyone confirm that my problem is likely with that solenoid and/or screen.... and if I'm looking in the right place for it?
This truck was scheduled to go in for an inspection sticker this week or next, I'm tempted to just hand it off to the mechanic for him to solve if it's going to be a pain. I'm sure I'm capable, but we're getting ready for winter so it's not a great time for surprises!

 

you can get to the passenger side screen in about 5 min. The driver side will take 45-1hr to swap because of the alternator being in the way.

see post 9 https://www.tacomaworld.com/threads/vvt-replacement.685602/

 

Have you checked the oil level?

 

I did check the oil- it's hard to get a good reading on that stick. could be a quart low, could be a quart high- but there's oil all over the dipstick.

Looking at that picture in #9 and comparing it to what I see on the truck, there's a square thingy that looks like its blocking off a passageway of some sort... and the image looks like it might be the top bolt? I can pull that off in a few minutes...

 

cleared the codes and went around the block- first time I gave it more than EASY acceleration (which come to think of it is when this happened yesterday too- usually I'm easy on the throttle) the CEL came on and it went into limp mode a few hundred feet later.

p0016,
and two p0011

I think I found the valve itself, but still having trouble locating the screen. Going to let it cool off a few hours and after work I'll try and check the passenger side valve...

actually, which side is bank 1? all of these errors are bank 1.

 

Bank one is the passenger side, definitely sounds like a sticky valve since you have both over advanced and over retarded codes.

 

Screen location
https://www.tacomaworld.com/threads/oil-control-valve-location.270960/page-3#post-15729126

 

well, I found the screen.

Every picture I see like that shows it... and it looks like it sticks out 90 degrees from the engine- turns out its pointing 45 degrees down, so it took me a good long while to lock onto it.
Took a 14mm short socket with a short extension to just barely have room to swing a ratchet in there, if anyone else is having a hard time...
it was VERY tight to break loose, and then it fought me the whole way out- as soon as it came out it fell and went somewhere (haven't found it yet)
while I was under the truck looking, I heard something else fall- the screen! at least I know I had the right bolt... Screen fell in the dirt, but it looks brand new after a quick spray with brake cleaner. even in the dirt it looked pretty clean, if you don't count the rock chunks.

Now I gotta find that bolt and put it back in- I guess the next thing to remove is the valve itself.

 

Yeah like @Dm93 said.
It’s probably the valve itself, since it had both advanced and retarded codes.
But it never hurts to check the screen. There’s been a few people get away with just screens.
But again, that was usually when they had 1 code. Not both.

 

I figured the screen would be easy to check on a quick break from work... easier than the valve- and if the screen was plugged then the other one would likely also be plugged, and both valves would probably be hosed up.

Screen looks great, but now I can't get it back in. Stupid fat hands.
Did find the bolt though- it was inside the P/S pump pulley. Tricksy.

Going to try to get it reinstalled again in a few... hopefully after work I can at least get the bank 1 valve out and see if its jammed- or unresponsive to voltage, or something.
I doubt I'd be able to source the part locally so I'd have to order it in anyway.

 

got the screen back in.
Is the OCV under the valve cover gasket? I might have to outsource this to a shop, working outside this time of year gives me pretty limited hours to work

 

They are under the intake. (Not the valve cover).
While it shouldn’t be a difficult job, you’ll probably need a few hours.
You basically disconnect the intake hose from the Throttle body, disconnect the hoses from the throttle body. (Some have coolant in them. Just pinch/plug them). Then unbolt the upper intake.
I’d say, if you’ve done it before, you could have it done in a couple hours or less.

I would recommend new intake gaskets. Sometimes you can get away with reusing them. But I don’t like too.
Especially on a vehicle more than a few years old.

 

Got the passenger side one out pretty easily

putting 12v into it, it jumps around- but wont stay open- always spring returns. I think its pooched.
going to see if I can source one locally tonight, if I hurry I might beat sunset...

 

no luck, nobody stocks parts out here best the locals can do is tomorrow, at that point I might as well wait a few days and order in from rockauto... gives me a little more time to make sure I'm testing this part correctly before replacing it.

 

Hmmm.

jumping it with some spare wire and a 12v tool battery, it seems to work just fine. Seems the jump wire in my little tool kit is suspect... glad now I didn't pull the trigger on ordering a replacement solenoid.

So if the solenoid moves freely and actuates when DC voltage is applied, and the filter screen is clear, that implies bank 1 VVT is working fine, right? Unless there's an electrical problem... I didn't notice any damaged wires when pulling this out.

 

It would set a circuit code if there was a problem on the electrical side of it.
Are you sure it's closing all the way? They like to stick partially open.

 

Likely a stretched timing chain. Clean the screens just incase.

 

Best I got for a comparison

I pulled the pic from the link below.
If you look close, you can tell the old one is stuck slightly open.
What ever you do, just don’t end up like the guy in post #13. Feel sorry for the poor guy.
https://www.tacomaworld.com/threads/1gr-fe-camshaft-position-timing.508832/

 

when unpowered, mine looks like the "new" photo- when powered it looks like the old... powering it only moves it about half as far as it moves if I push the valve with a screwdriver. No idea if that's normal or not.

 

I replaced both at 150k engine felt peppier. With your issues, I’d replace them both as well.

But, with those symptoms I’d also pull the valve covers and check timing to ensure you’re within factory tolerances. How many miles you got?