Misfires, urgent help needed!!
 

So, engine runs like sh*t, stumps at idle but basically over 3k rpm there's no hickups...
Codes thrown:
P0040 Oxy sensors in front of cats changed
P0130 O2 sensor ahead of cat bank 1
P0300/0301/0302/0303 Misfire detection total/cyl1/2/3

Then from Durametric, engine idling:
Camshaft position 1 deviation 0.14 deg Crk
Camshaft position 2 deviation -4.59 deg Crk
EDIT: Unfortunately I did not check actual cam values when engine was running.

So, is it the camshaft position sensor or adjustment solenoid at bank 1? I'm in a bit of a hurry, there's this Time Trial I was about to attend next weekend...

EDIT: I have checked that both cam actuators operate when 12V is fed directly, their wiring is also OK, like wiring to Bank 1 Cam Pos Sensor. As per WSM's test also the LH O2 sensor seems to be OK. LH Valve actuator bracket is OK and the actuaror moves is 12V is fed directly. So it's either the Cam Pos Sensor or something more serious.
BTW, I just changed to Castrol TWS 10W60, does thicker oil have any effect on VarioCam Plus' operation?

Sounds like your cam bracket is broken or cam sensor is bad or timing chain broke.

have you checked the fuel pressure? ~ maybe fuel pump is dying, split hose - at low rpm car runs and bugs, it can throw all kind of errors, dirty TB?

coil packs and plugs

Nah coils and plugs wouldnt fail on just bank 1 like that on all those cylinders.

No sweat. We run that oil all day here. Absolutely no problems at all.

Those cam numbers are on the high end of deviation but on these engines there is usually a degree or two of difference. They are never identical no matter how carefully the engine is assembled. Yours may be a tooth off but that isn't your issue. Have you checked your o2 sensors ahead of your cats?
An easy test would be to swap them between banks.

Doesn't Manthey run TWS10-60 in all their GT2/3s also? I've been thinking about trying it out. I run M1 5w50 but I'll see oil temps peak at 260F on long track sessions in the summer. Curious if the TWS would be better...

Move on, move on, there's nothing to see here!

But if you're still around, this was a quite good guess:
Namely after teasing/clicking all actuators with direct 12V, replacing LH O2 sensor with another (used) one and adding a new gasket between TB and IPD plenum, the engine runs now quite nicely, thank you.
The previous gasket had gone with the wind -or boost...it was still there, but severly damaged and streched and the TB was loose. Reason unknown. Noticed this just by a chance, before starting to drop the engine.
Lambdas in both banks are now normal, as well as camshaft angles. No deviation there anymore.

IDK about Manthey, but most Turbos here I know run either M1 5W50 or Castrol 10W60. It would be interesting to see if a change would help with your high oil temps, but I doubt it.

My car used to have a separate oil cooler in the front (which I took out). If you often run into oil temp problems, that solution might be an option for you.

260 is not a problem as far as oil temps go. I only get that on 100+ degree days at the end of 30 min sessions. Just heard good things about TWS 10w60. Might try it for the hot summer months..

https://www.6speedonline.com/forums/...-misfires.html


It the bracket or the variable valve lift . Have had it before. Disconnect the connector and put it on . Do that a few times .

The high oil temps -- 260F ain't that high btw -- could be a sign the oil is doing its job.

The oil comes in contact with the some of the hottest parts of the engine: the underside of the pistons, the valve stems, the rings, the rod/main bearings, and part of its job is to remove heat. Thus elevated oil temps is a sign it is doing this.

Going with a thicker oil while one could see lower oil temperatures it could be because the thicker/higher viscosity oil is not able to absorb heat as well and thus the hot parts of the engine are running hotter than they would otherwise.

260F is high for oil temps.

Glad to hear you've resolved your problem. Those gaskets can cause some loss of boost if deformed enough and I keep a spare on hand. In your OP everything seemed to point to the left bank pre-cat o2 sensor though.
The Cam deviation being within a few degrees is normal and if you see it again don't be too concerned.
I've gone through so many misfire troubleshooting sessions on different cylinders over the years I have lost count.
In the beginning I couldn't tell who knew what they were talking about or who was just guessing when I would post to ask about my misfires but now certain symptoms under specific conditions along with Durametric diagnosing misfires has become far less frustrating.

I don't want to start another oil debate...there are hundreds of 6S0 and rennlist forum pages dedicated to this topic, but running such high viscosity oils (10W-60) in the 996TT engine can lead to problems with Variocam plus opearation. The dual-lift intake lifters in particular are sensitive to this and can fail to operate properly if too heavy an oil is used. The oil passages that operate them are just too small.
Maybe if your car is used exclusively for tracking and oil temps are hotter than the average daily driver 10W-60 isn't a problem, but even then I was under the impression that heat is what cause all multiweight oils to gain viscosity up to their max rating, and 60W is far greater than the max recommended for our cars.
Mobil 1 5w-40 turbo diesel truck is a full synthetic and has the critical zinc levels that aren't present in their 0w40 in the current formula.

I agree on this i forgot where they were talking about the oil being to heavy and bad. I run 5w 40 motul and thats it.

I guess this picture answers the question whether or not 10W-60 oil is suitable for Mezgers...


https://cimg9.ibsrv.net/gimg/www.6sp...4eaf09a9f1.jpg

you have no idea what the clearances are in that engine.

I sincerely doubt that RUF has altered VarioCam Plus's clearances...

bearing clearances. Bearing clearances are one part in dictating oil weight.