Code P1519... ?

[filmy]

'98 328iC

I finally broke down and bought an Actron OBDII code reader because I got tired of stopping by the mechanic to read/clear my code(s). (I think $60 is a pretty good investment for this tool.) Anyway, to the code(s)...

Along with:
P1189 (air fuel metering), and
P0173 (fuel trim bank 2), and
P0154 (no signal from O2 sensor 1, bank 2 - upper, rear)

P1519. Actron lists this as "Manf. Cntrl. Veh.Sped. Idle Speed Control Auxiliary Inputs" What means this?

The first three codes seem to have something to do with a vacuum or intake air leak for bank 2 (rear). If P1519 is creating an irregular A/F mixture, then those codes might disappear if I can find out what's leaking or not functioning properly. But if the problem is related to the intake or ISC, wouldn't I be getting codes for both banks, not just bank 2...?

Perplexed. :(

MPG pretty steady at 20-22, so I don't think the problem is too severe.

Possibly of note: when I had the intake boot and MAF off yesterday (to clean and check for cracks) the throttle body had the inner brass flap completely sprung open (car not running, of course) and I thought this was odd. It moved/closed by hand, though. Normal?

P.S. After writing them down, I cleared the codes and they didn't come back - yet - after 30 minutes and 10 miles of driving (I'm in LA - sue me).

Edit: Bump for the codes coming back today (next day). As expected. :(

[filmy]

Update. I think I've found the culprit to my codes. Generally, the first three:
P1189 (air fuel metering)
P0173 (fuel trim bank 2)
P0154 (no signal from O2 sensor 1, bank 2 - upper, rear)
are air/fuel mix related, further that I have a vacuum leak somewhere. After following my vacuum hoses all over the engine bay and replacing what I felt might be leaking, nothing changed.

But in asking about the vacuum hose going to the exhaust flapper, I found that there's an electrical switch in the trunk that allows the vacuum to open the flapper (see "golf tee mod"). It's under the plastic "floor" of the trunk on the left/driver's side. A hard plastic vacuum line comes to the switch from behind the rear panel of the trunk - which then allows vacuum out a rubber hose to the exhaust flapper underneath the rear bumper cover. With the car running I heard a hissing there, and sure enough that hard vacuum line had been almost severed in two (can't imagine why, but...) I tore off the damaged end and plugged it back onto the switch. Now my exhaust flap closes when it should (one of my first visuals that there was a problem). I may or may not do the golf tee mod, but if so I'll plug the vacuum line in the engine bay (the line that goes underneath the fuse box.

P1519 is most likely my vanos in need of a re-seal. I'll report back about canceling the codes if these repairs prove to kill the CEL.

[filmy]

As an update for anyone dealing with these CEL codes (P1519, P0173, P0189, P0154)

P1519 shows: "Manf. Cntrl. Veh.Sped. Idle Speed Control Auxiliary Inputs", or camshaft position actuator (depending on what you found in your search). This is a stuck or non-functional VANOS. I did the Beisan VANOS seal repair yesterday and the code is now gone. I can't say if the VANOS piston was either jacked (stuck) in the bore in advance or non-advance position, nor if the oil pressure was simply bypassing it by due to worn seals, but the code is now gone and hasn't come back. Engine pick up during advanced timing is noticeable.

The other (air/fuel) codes were erased when I installed two new matching NTK pre-cat O2 sensors.

[dano670]

Nice that you posted some results from your after rebuilding your vanos. Glad it fixed the problem.