Check engine light on and code P1346

Hi,

I looked through the freeze-frame info you provided. Everything looks okay. So, I have a feeling you are correct, timing.

If you at the attachments below, they show the diagnostics for the code. The primary step is inspecting timing.

Take a look through the diagnostics and let me know if you are comfortable performing them.

Take care and let me know.

Joe

See pics below.

The common reason for that code on the 1.8 is a stretched timing chain. The code really means that the camshaft timing is out of sync with the crankshaft location. So the crankshaft might be at top dead center on number one cylinder and normally the camshaft might be 10 degrees before that (or similar) in this case the code sets because instead of the computer seeing the signal there it is showing up at 20 degrees when the crank is at TDC.

There is an easy way to tell without removing any parts but it isn't a test many places can or will bother to do. It involves using an oscilloscope connected to the cam and crank sensors and you look at the actual signal from each. Unfortunately most shops don't bother to use a scope and will instead tear the engine apart, then tell you, "yup the timing chain needs to be replaced for $XX".
For the DIYer the easiest way without a scope is to remove the valve cover and set the engine at the proper position and then look at the timing marks on the cam sprockets.
For that you remove the engine trim cover, then the ignition coils, then the PCV hoses, the bolts for the cover and then the cover. Next you rotate the engine so cylinder 1 is at TDC and the timing mark shows at zero degrees. Then you look at the two timing marks on the sprockets. They should be facing each other and setting level with the edge of the cylinder head. Although this sounds like a lot of work it only takes about 1/2 hour to do. I suspect you will find the timing marks off like the third image, instead of being in the position of the black dots they will be like the red dots or not visible below the lip of the cylinder head due to the chain stretch. At that point it becomes a choice, this engine is an interference design, if the chain and timing components are replaced now it should be okay until something else wears or fails. However if the chain wears more and then fails, you would likely be better off replacing the entire engine as it will damage the cylinder head and the timing cover at the least.
I'm sure Joe can guide you through the swap of the chain. I just wanted to let you know that it isn't a minor problem if ignored. Not saying you would but many people do, they will drive with the check engine light on for years, then complain when the engine expires "for no reason".

Normally if it is the VVT you wouldn't get just the correlation error. You would get an error that shows the timing as stuck in one mode or the other or a circuit code for the solenoid.
Oil burning is a pain but with that mileage it's not surprising given how they build engines these days. Have you tried doing a top cylinder cleaning to see if it might free up the rings a bit and slow the oil use?

Oil in the connector isn't a good thing, but it's doubtful that it is the problem. It could change the amplitude of the signal but it isn't going to alter the signal itself as that is a digital square wave that counts the raised tabs on the sprocket. Myself I would grab my scope and check it but not everyone has one on the shelf.
However it's not that bad of a job to pull the cover to verify the issue either. If it is a stretched chain it can fail at any point and then the chain causes a lot of damage.
As for it being the VVT, not likely to be that because of the way the system operates. If it was the VVT sticking the engine would run very poorly and you would have more than the single code. More likely the oil change is causing the VVT to operate better and now the PCM is seeing the same error it saw prior to the new sensor. As an aside, when you replaced it the first time did you also reset the memory so it learned the position and signal levels of the replacement sensor?

Okay, if it's running that way it's possible it's already out of time some. If you can find a scope to use you can look online for YouTube videos showing how to do the testing, look for scanner danner, new level auto and pine hollow auto diagnostics, all three show the process and describe what to look for in more detail than I can type. A scope would also show you if it was working because you could unplug the solenoid while watching the signal and see if it moves in relation to the crank signal.

Could be some sludge found it's way in or more likely a bit of varnish formed in the VVT actuator and the MMO freed it up. The only issue with that is, it may cause other build up to move as well. I would probably change the oil again just to remove it. Exhaust work is always fun, especially in my area where the salt eats everything.
Good to hear it now is running good. Thank you for using 2 CarPros.