jmh981

Maybe you are driving it wrong....or expecting too much at low RPM. Who accelerates on an on-ramp at 2500 rpm?? Torque is weak down low, maybe that's what you feel. The only time I would be accelerating from 2000 - 3000 rpm would be putting around town.

STG

That's a great point.

The X51 has a different plenum than the non X51 cars too. Not sure an IPD Plenum would do the trick to solve this issue. Seems more to it.

Somebody needs to figure out the correct diagnosis. I'm surprised it's taken so long. Don't leave it up to PCNA. They don't care now that 991.2 is coming. Didn't care a few years ago either. I think they believe if the problem isn't widespread enough, it's a non issue. I'm sure they know what it is.

They still have GT3 issues popping up and uncertain future ones at this point, and the sister company drama as well. Bigger fires to contain.

stealthboy

You are part of the reason I stopped posting about it. This doesn't help me, or anyone else with this problem. Please stop. I'm not going to redline it in my neighborhood at 6am while leaving for work.

Surprise, surprise. There is driving to be done below 3000 RPM. It's not weak torque that I feel. You obviously do not have the issue.



I would love to know how you never let your RPMs drop below 3000. Please explain. Do you drop your clutch at every green light?

duxsi

Very true..

997s07

It's wise to ignore dipśhit posts. Don't waste your breath on them. Help, and ask for help. Ignore the clutter.

duxsi

Very very true...

I need to attend the ******* School of Driving in order to learn how to properly utilize the powerband between 2500-3000 rpm..

STG

With so many good independent shops, I can't believe this thing should be hard to diagnose. Anyone ever had it looked at by a non P dealer who isn't going off the talking points memo?

96redLT4

Your summary details it very well. I hope someone can help these guys
J

96redLT4

I had read somewhere, maybe on 6speedonline, that upwards of 10% of cars may be affected. Responses so far would seem to confirm this. I tried to drive mine very carefully but did not notice anything from 2-3K. Only about 500 miles on the clock so far though.
Jim

stealthboy

I mentioned to PCNA that my next step was to take it to an independent shop and they basically threatened me with possible void of warranty.

STG

That's BS. Having an independent shop look at it and diagnose isn't going to void any warranty. Geez. Not like they doing to take apart the whole engine. Does an independent shop oil change void the warranty too? I'd have it looked at.

Some of these PCNA tactics are on the verge of being "dictator like". They should be afraid of a lawsuit more than anything. Oh geez, already on the way with diesel gate. VW sales down 25% in Nov.

http://www.worldcarfans.com/11512031...25-in-november

Like I said, they have bigger fires to extinguish.

Larry Cable

might be worth trying it though ... although I would think that if such a component change cured this then *all* non-X51 cars would suffer from
this problem (since the plenum is a static part) so there is something else
going on if you ask me...

I wonder if there is any telemetry that could be extracted from the OBDII
CAN that would at least illustrate the problem when it occurs ...

the fact that this occurs around 2500-3500 rpm occurs does suggest some
issue with the intake or exhaust, as this is I believe when varioram/cam
and the exhaust switches over...

if no X51 cars had demonstrated this, I would suggest its intake related, but
since we have evidence that this is not the case, I dont think we can pinpoint
the problem to components that are not shared between the two engines

For PSE equipped cars, has anyone tried to repeat the stumble with PSE "on"? - i.e the exhaust flaps always open? - that would eliminate the
exhaust as a possible issue... so it would be intake/cam related

(another thought - is this only with 'S' cars or also base models?)

STG

I hope this issue picks up steam here. The 6Speed thread on it is amazing. Unfortunately, 6Speed has turned into a graveyard over the past year. The only hope for discussion is on RL here.

To some of the guys who have been at it for years, it may take some catching up for some of the guys on RL. Be patient. Overall, the knowledge of some of the guys here is amazing.

I hope some answers can come soon for all involved.

Money2536/Matt's old car had it and he wrote extensively about it on 6Speed. Got fed up and traded in for a GT3.

duxsi

I've has tried it with PSE on and off. No difference.
The fault exists with both Base and S models.

It is definitely not the vario-cam blip at 3000rpm.
This occurs before that and feels just like when we used to have a vacuum line issue in the old days.

Also note, when the DME is reset or the battery is disconnected overnight, the problem goes away. But once you drive the car again for a couple of hours the stumble returns.

So the DME is compensating or trying to correct something...

duxsi

Forgot to mention that when cruising at ~2600rpm on a slight incline (with or without cruise control), the tugging starts. This sensation almost feels like fuel or O2 starvation.

Another owner has had his throttle position sensor replaced and it made no difference, so a faulty TPS has been ruled out..