DeadEric wrote: ↑
Wed Apr 17, 2019 5:45 pm
Sounds like your cam phaser is advanced and you have a bad vvt solenoid by what you said before you cleaned it. Being a device that uses electricity to move it mechanically, ohm checking it is half of the equation. If you'd like I can explain how it works in detail
but I'm trying to keep this short. Cleaning it the way you described could not only damage the solenoid but allow the gunk to flow past the screens and into the phaser.
Yes, please expound, you seem pretty knowledgeable. What part of MN are you in?
My original solenoid gasket was the non-screened type, and my original solenoid was flowing clean when I reinstalled it.
I don't know if you watched the short clip I linked with the guy that had the play in his VVT hub, but I had a fraction of that amount of play. So, yes, I agree with you that the VVT hub (aka phaser?) is probably going to be the next piece to fail/replace. I assume that since this part isn't in perfect mechanical shape that IT is responsible for the "lurch" in power felt around 1,200 rpms.
I don't really see how a hall effect sensor like the cam position sensor(s) can go bad, but I'm sure it has happened. De/polarization.
Again, I really can't say exactly which component it was (or combination of) that led to my resolution but I'm happy & just kinda going with it for now. Replaced VVT solenoid, retarded intake timing 1 tooth, replaced BPV, re-secured vacuum line to nipple on intake pipe that goes into turbo, changed oil.
You also mentioned that it ran better off idle. This is normal, higher rpms is when the phaser would activate and advance (usually with load.)
Lastly, with the P0014 setting immediately after code clearing, the non continuous monitors will not run. Meaning other codes will not be tested or set until this is fixed and a drive cycle is run. Cat and evap test are usually the last to run.
I do think that the cat was partially occluded when I first got the car. The scanner did show a cat code. This would make sense seeing as the car had been driven a while with the dead #5 ignition coil, on top of the fact it had been driven a year or more with the intake timing off. In fact, the exhaust note actually sounded different than our other XC's/muffled or plugged up sounding prior to any of my successful repairs/trials. The first few drives I took it for (after making successful adjustments), when I'd get back in the garage & pop the hood the exhuast was really really hot. Gradually the temp would come down & engine temps actually came down also from what they had been previously (were ~190 H2O temp, now runs around 182-3). After having driven the car maybe 1-1.25 hours the exhaust note has now changed, as in normalized, sounds just like any untampered with XC70. So strange. So I'm guessing with enough heat being generated & the engine running as it should the cat has sorta gotten cleaned out.
Vida will actually map the cam position for you and tell you exactly what is going on.
I would have thought that the cam error would be triggered only by the sensor position but maybe the ECM algorithm is more complicated than that.
I think I’ve read here that up to three notches on the cam sprockets are safe in terms of interference so bumping a notch or two is safe.
Since there's not a sensor on the non-VVT cam (intake, in my case), yeah, they must account for it based off the exhuast cam's position.
Well I can attest that even being off on my exhaust AND intake cams by 1 tooth each (at the same time!) no piston to valve contact was made! Thank God!