ParisAudi

hey guys, hopefully someone is able to assist me with the following issues:

The other day the car was driving all ok, i parked up and went into the gym.

When i came back out and started the car i was greeted with the below errors:
p0014 - camshaft position (bank 1) timing over advanced or system performance.
p12a3 - Fuel rail pump control valve control valve stuck open.
p0366 - camshaft pos sensor "b" circ. Bank 1 range performance.

I cleared all the codes and the following codes came back straight away:
p0014 - camshaft position (bank 1) timing over advanced or system performance.
p0087 - Fuel rail/system pressure - too low

I replaced the plug on the camshaft exhaust bank 1 actuator and cleared all the codes.

Now the code is showing:
p0017 - Crankshaft Position-Camshaft Position Correlation Bank 1 Sensor B

When this code is present the engine will not start/crank by pushing the button, holding the button will allow it to start after about half a second to a second.

If i clear this code then i can start the car with the touch of a button, the code p0017 will either come back once started, or i will have the following code:
p0366 - Camshaft pos sensor "b" circ. Bank 1 range performance.

If i unplug the cam sensor i get:
p0368 - Camshaft Pos Sensor "b" circuit (bank 1) high input.

I can see the cam sensor exhaust bank1 is reading on VCDS, however i notice when bank 1 shows as -25, bank 2 will fluctuate between -24/-25 (when the expected value changes it will match it), and when bank 2 shows as -25, bank 1 will fluctuate between -24/-25, for some reason both wont work at the same time, is this expected?
(There was a time where the expected value of exhaust bank 1 stopped working and was showing -25. It did come back but weird)(did record videos but didn't save properly) can try to get it again.

All the errors are on bank 1, nothing on bank 2 is showing as having any issues.

The car drives fine (very slow albeit) (in limp mode 2.5k max revs) but no unusual noises etc.

Really strange, I'm starting to think there is a wiring or ground issue but where do i even start to diagnose this?

Really hoping someone has some advise.

I also changed the battery on car to see if it was voltage related (due to battery being weird when charging and battery health was showing replace).


Will continue debugging and try to get some recordings of VCDS logging the issues.


When out to record the debugging of the actual and expected/target values and bank 1 and 2 were targeted at -25 (bank 2 went to -24 under revs) whereas before it was going to -13.
Really random, we're calling it a day for today and will look at it again tomorrow, starting with probing the wires from sensors to the ecu, to rule out any wiring issues that could be happening.

Any suggestions or extra things we could try tomorrow would be great, thank you.

Will keep you posted.

ParisAudi

Car is a (S4 B9 2018 April build)

njspeedfreak

Since it;s a 2018, I have to ask .... Any loud metallic clicking noises at idle prior to the car throwing codes?

On the 2018's that have the bad rocker arm bearing, once the bearing seizes up and starts creating excessive wear on the cam, a lot of the metallic waste ends up getting picked up by the magnetic cam position sensor. That's what happened to me. Went into limp mode, showed a sensor error, but the actual problem was far worse than that.

ParisAudi

Yeah I have the same issue with metal on the sensor. It's being trailered over to a specialist on Saturday to inspect the engine damage as clearly the rocker arms have failed and damaged the cam also.
Pretty annoying Audi wouldn't recall these rocker arms.