E85 - VANOS Unit / Persistent issues - HELP!!

SloanRH4 · Post by **SloanRH4** » Tue Jun 01, 2021 5:15 pm

To me it looks like the camshaft sensors, I've seen a lot of people that had problems with rpm "stability" to fix it with camshaft position sensors. Keep in mind that some of the sensors, although new, don't work very well, if I'm not wrong Hella ones seem to work fine (except for OEM, of course). What I can't relate it to though is the DSC error... my other guess, since you seem to hay 3 different problems that might be unrelated (camshaft sensors, DSC and lambda) would be the battery, when it's not working properly car throughs a lot of different errors, but you said you already checked that...

Zulu4 · Post by **Zulu4** » Tue Jun 01, 2021 6:44 pm

I definitely got DSC errors when my solenoids were playing up. Can't explain why though.

Ricardo1992 · Post by **Ricardo1992** » Mon Jun 28, 2021 8:36 pm

Right, still no idea what the issue is. So far, changed the solenoids within the VANOS unit, the camshaft sensor, o2 sensor, o-rings at the bottom of the fuel filter and all seals within VANOS unit.

Checked both VANOS exhaust and inlet positions which seem to be stuck at 11.00% even when gas is applied. Checked electrical lines to both solenoids and reading exactly what they should. So thoughts is that its a mechanical issue and not an electrical.

Anyone got ANY idea of what it could be? Feels like every option has now been explored and no fix. I am at the point of almost giving up with the car....

bigwinn · Post by **bigwinn** » Mon Jun 28, 2021 8:59 pm

Hi bud

Read your issue before- sorry to hear you are still having issues

The only other angle I would say check, from my experience.

Have you dislodged or damaged any of the ccv kit?

When I did my vanos (1st time) I made a schoolboy error with the oil filler cap

That made the engine run poorly on deceleration and it threw lean running bank codes

May be nothing but it took me a while to see where I’d c0cked up

Stuart

Ricardo1992 · Post by **Ricardo1992** » Mon Jun 28, 2021 9:18 pm

bigwinn wrote: ↑Mon Jun 28, 2021 8:59 pm Hi bud

Read your issue before- sorry to hear you are still having issues

The only other angle I would say check, from my experience.

Have you dislodged or damaged any of the ccv kit?

When I did my vanos (1st time) I made a schoolboy error with the oil filler cap

That made the engine run poorly on deceleration and it threw lean running bank codes

May be nothing but it took me a while to see where I’d c0cked up

Stuart

Hi Stuart,

Thanks for your comment. I have checked the CCV kit and from a visual inspection, there doesn't appear to be any damage. When taking the breather off to remove the VANOS, this was done successfully and without any issues.

Ran a full ISTA+ scan on the car trying to narrow it down. However, the one thing I cannot seem to be able to do on the M54 engine is check the oil pressure with the software. Checked battery voltage, Oxygen sensors, etc. One error I did get was when triggering the Camshaft position controller intake and exhaust. Error being "ERROR_ECU_CONDITIONS_NOT_CORRECT_OR_REQUEST_SEQUENCE_ERROR" for both...

Mike6 · Post by **Mike6** » Tue Jun 29, 2021 3:11 pm

Strange that engine is very loud and if you focus on that could it be a burnt exhaust valve. Not sure whether that would trigger other fault codes. A compression test might help to eliminate possibility of engine problems. Ignition timing being out would also affect engine noise but most of my experience is on carb cars so not sure whether timing can slip on these cars. Given that the VANOS does have some impact on timing (??) that could give a clue.
Hope you get it resolved soon.

enuff_zed · Post by **enuff_zed** » Tue Jun 29, 2021 3:21 pm

My question would be why are the cams both set at 11 degrees?
Is this a default setting when the ECU detects a fault? A kind of limp home setting perhaps?
Although you checked the solenoids for a power supply, could it be the ECU is supplying an 11 degree setting power?
Or is it possible that although the solenoids are working and the valves are applying oil pressure to the Vanos, it is not actually moving.
Did it all go back together correctly?

Please note, I am brainstorming ideas that may provoke further thought. I am not saying this IS your issue.

Ricardo1992 · Post by **Ricardo1992** » Sat Jul 03, 2021 6:26 pm

Got an image of the INPA diagnosis. Anyone make any sense of this?

Benderloch · Post by **Benderloch** » Fri Sep 10, 2021 7:29 pm

Did this issue get resolved?

Ricardo1992 · Post by **Ricardo1992** » Fri Sep 10, 2021 7:46 pm

Benderloch wrote: ↑Fri Sep 10, 2021 7:29 pm Did this issue get resolved?

Still not resolved. But will be going to the garage tomorrow. My local garage couldn’t pinpoint the problem either. Will give an update on what the problem was once it’s fixed!

Mike6 · Post by **Mike6** » Sat Sep 11, 2021 5:09 pm

When you say battery has been checked and all ok I had problems, not the same as yours but turned out whist battery was showing correct voltage it was down on amps. A new battery solved the problem.

Wortmanov · Post by **Wortmanov** » Tue Sep 14, 2021 12:45 pm

Following this - I recognize the issue with the louder exhaust note. I am going to be looking at the contacts soon (connectors getting old).
Reading this, I am wondering how the VANOS oil supply works.

Did you also try to activate the VANOS in INPA to see what happens? The error you had in ISTA almost suggests that one of the conditions for VANOS activation is not met. Does the DME throw any other fault codes?

Wortmanov · Post by **Wortmanov** » Tue Sep 14, 2021 1:09 pm

I just looked at my collection of pdf's for the Z, and I did find some documentation around the vanos. Perhaps it helps.

Z4-forum.com

Z4-forum.com