VVT Woes, and Bank 2 issues...

['10CamaroDude]

So, on Monday I put a new VVT Solenoid in bank 2, exhaust side, cleared
the CAT code. Started it up, It popped up P0023, VVT short or open. When
first started, ran bad, misfired, back-popped, set all bank 2 cylinder misfire
codes, then poof, it ran smooth, and didn't have any issues shutting down,
and starting it up a few time afterwards, nice smooth idle, and less valve
noise. Cleared all the codes, started it up a few times again, and P0023
popped up, that was all there was. So, I ran it...

Well, the car ran like a bear all night! Held 6th going up hills a lot better, no
shudder in the engine under load, and? That pesky P0430 CODE, never set!
I ran it 376 miles, checked the ECU three times for the code, all that was
there was the P0023 code.

AS it turned out, The VVT was broken, the end head spun independently of
the chamber. When I put it in, it has to be turned to the mount hole, but
you can't put it in already lined up with the belt in the way. Well, it got
stuck, but it broke loose, turned it, and I could line up the holes and
tighten.

Unbeknown to me, the end had broken loose. So, the end or oil chamber
portion was not even in the engine clocked in the right position for the oil
passages to the cam phaser. However, as I said, the car run good, and no
no CAT code all night...

SO yesterday afternoon, went to pull that VVT, and it was stuck. The head
turned, but it was stuck. I had to pull it out with pliers. That's when I saw
the head spun freely of the oil chamber.

So, I put a cleaned factory VVT back into the exhaust cam side cam, and
ran it 376 miles last night into this morning. Car ran like it did before, still
power and torque, but there was the engine shudder under load up hills,
and it would not hold 6th gear long going up gradients and hills. AND? The
P0430 set two times. First, after running 174 miles. I reset it at 188, then
it set again at ~288 miles.

I put TWO brand new ones in bank two THIS afternoon. Will see how it
runs tonight into tomorrow.

With the solenoid showing SHORT or OPEN, I don't know if that means the
cam phaser was neutral, or advanced for the P0430 code not to show up.
One symptom of a CAT code for efficiency below threshold is retarded
exhaust cam timing.

['10CamaroDude]

Another brand new solenoid, still get P0023. However, P0430
did not set.

If I put any of the original three back in, I don't get the P0023
code, but then I will get P0430.

There is no short or open condition. I read duty cycle can also throw
the code. IT will store the code when driving, but the CEL will not come
on until the next drive cycle.

The car runs so much better when the code is set. Which would be
fine, but I won't pass emissions with a CEL on.

[Mouse330]

The ECM will not test for catalytic converter efficiency if the p0023 is set

['10CamaroDude]

Originally Posted by Mouse330

The ECM will not test for catalytic converter efficiency if the p0023 is set

Yeah, that's kind of what I thought. No matter what new VVT I install,
P0023 comes up. Only the original ones that were in the motor when I
bought it, work in that position. I have three of those... All four are new,
now, but the exhaust side bank 2, won't work with a new one.

['10CamaroDude]

Fixed, I think. Code cleared, and did not come back after a few start/stops.

I retested everything, and there was no resistance on the new VVT coil. The others
were 8ohm. I also found a fluctuation in the voltage at the harness. I pushed the
contacts in so it made better contact, and got a steady 10V on the meter. It all
tested fine from the beginning, so it was a combination of harness and VVT.

Factory VVTs were 8-10 ohm, so the replacements are within that tolerance.

[Mouse330]

nice,good job

[mikeman]

I wonder what caused the VVT actuator to break like that. How many miles on the car?