Porsche fault reported in newspapers

[colski1961]

there was lots of talk on PH's about this a while ago, relating specifically to Cayman R, which I was an owner of at the time and I went out and tested to see if I could make the delay happen. My Cayman R PDK, if driven correctly, never had any delays. It might be that if you have it in full auto, not using paddles or sequential, non-sport mode, travelling at 30mph and then just expect the car to pick up by pure throttle response then there may be a delay but if you're planning an overtake surely you would drop a gear or two and prepare? I don't think PSE played a part as it doesn't kick in until the Sport or Sport+ are engaged anyway (correct me if i wrong but that was my experience).

Lots more coverage on this on PH's (just read again) but my view is, if you have a sports car then drive it as such.

Just my 2 pence worth as a former owner of a great Cayman R PDK.

Colin

 

[Buddy]

A fault has been reported in some newspapers where a 2011 Cayman failed to accelerate from 30mph supposedly putting it in a dangerous situation as it effectively stuck as if in a throttle jam for about 2.5 seconds, it was said that due to noise regulations Porsche have a throttle delay which can cut in some situations.

Have any members found themselves in this situation?

As is usual the paper failed to state what engine, transmission or exhaust system was fitted in the car and someone else stated they had a similar event. Nothing more!

I believe the 981 has PSE that is switched off automatically when speed is reduced to 30mph but in the 987 maybe a software tweak to stay within regulations could cause the problem, if we can identify what the problem is then we can switch them off where speeds are expected to be lower.

 

[MrDemon]

it's only in 4th gear at 28 mph , if you are at 30mph in 4th gear buy another car

You can make any 987.2 manual do it, I had a go but it's quite hard as you have to be going dead on that speed then floor it.

99.999% of people would never know as no one floors a car in 4th at 28mph !!!

 

[Buddy]

Interesting, in 4th at 28-30 you're so far off the power band that you're not going anywhere fast and true that you shouldn't be in that gear, even 3rd is just pulling around 2,000 at that speed so to accelerate you still need to drop a gear.

Sounds like people who don't know how to drive using the power band and gear ratios only driving in full auto. I have PSE which is on or off not speed related operation but the 30mph reference made me wonder if that was Porsche's fix, to make it switch off below that speed.

I have the Chrono which brings on the PASM but not the PSE which is switched independently. PASM can be deselected if a softer ride is wanted ( generally when my Spaniel is in the passenger seat as he gets a little queasy, he'll get used to it ).

 

[Brian_Innes]

Mr D is quite right.

CR drivers are not in the habit of accelerating in 4th gear from 28mph. We are not diesel drivers.

I have never experienced this so called fault ever in 26k miles of driving my CR manual with PSE.

A totally pointless newspaper report IMO. Pandering to the ignorant.

Brian

 

[Buddy]

No one who drives properly would be in 4th at such a low speed CR, CS, 2.9 or 2.7 no difference, labouring the engine will only cause damage. In the days when we had carburettors engines couldn't pull from low speeds but the modern engine management systems can pull from 1,000rpm it doesn't change the potential mechanical impact of loading an engine when it's not at a sufficiently high speed to cope, in the Gen1 987 & 997 it caused bore scoring as the oil pressure was insufficient at the low speeds, the Gen2 has improved control of the oil supply. But to accelerate it's best to be around 2,000-3,000 if driving lightly even in traffic, for performance driving the torque doesn't come in until 4,000 then the fun begins

 

[duncanireland]

No one who drives properly would be in 4th at such a low speed CR, CS, 2.9 or 2.7 no difference, labouring the engine will only cause damage.

Not sure I agree with this at all. My CR is perfectly happy in 5th at this speed never mind 4th - indeed the economy indicator demands you change up to 5th ;-) Engine's not even vaguely laboured.

Obviously, were I to need to overtake someone from such a low speed then I would be going down the requisite number of cogs.

 

[Buddy]

I rarely drive my PDK in automatic mode as it is too slow to react to a request to accelerate, at 28mph in 5th the engine is turning at approx' 1,400rpm ok going downhill maybe below that speed it is likely to change down or the engine will start fueling again since above that speed Porsche usually stop fuel on a closed throttle but to actually have load on the engine potentially damaging. Just because the engine will run smoothly at that speed doesn't mean it is happy about the situation.

 

[Motorhead]

Kevan,

I've not seen the article but this sounds suspiciously like a defeat device to get round the pass-by noise regulations. Oh no! Here we go again...

Jeff

 

[Buddy]

Precisely what I thought at first Jeff but it's when people are doing 28-30 in 4th gear and expecting it to just accelerate to overtake! At that speed to overtake I'd be shifting down to 2nd.

 

[flat6]

This 'revelation' sprung up in 2011 & again in 2012. If someone is raising it now they're just pedalling an old discussion. As MrD said, it was isolated to a scenario that you wouldn't perform.

If you Google 'Cayman R turbo lag' you'll find some very old results returned.

 

[Motorhead]

Agreed that it's something very few - if any - of us would do, but perhaps it just goes to show the lengths to which manufacturers go in order to comply with (or circumvent?) regulations.

Here's an interesting quote in connection with the current pass-by noise regulations:

Moreover, the current Regulation 51.02 allows tuning a vehicle such that power output is suppressed under the exact test conditions, just staying within the allowed limits for this condition, thereby negating the usefulness of the standard in limiting noise in real life conditions.

Jeff