Took my 8 out for a spin had it nice and warm and on the return, after 5mins creeping up to the lights thought i'd let it rip on green as there was nothing in fron of me.

The severe lack of power and fluidity in acceleration actually had me checking if i had left the handbrake on full! It took a good 15mins of further driving before it seemed to come back to 90% efficiency.

There was no evident good reason for the 15mins of power loss, the only other time i noticed it was when i tried unleaded 95 and again it pretty much drove itself out again (later i topped it up with 100 just incase).

Anybody else have this problem or know why it happens?

 

Could be contaminated fuel--like water in it. Could be the infamous fail-safe mode. Did you get a CEL?

What country are you in? They must use a different method for rating octane. Never seen 95 and 100 octane here in the US, at least at the pumps.

 

hmmn, from what i read it doesnt sound like the fail-safe as it was driving at 5000-6000 rpm but felt like it was running with one leg tied.

 

ive felt that before too..... but i wouldnt say it was as extreme in my case. i lost maybe 20% power, and my exhaust note sounded very nasal and restricted. after i ran it through the 4-6k rpm range a few times i began to notice some rattling sounds which i believe to be pinging as a result of carbon buildup. i had been running some pretty cheap gas also, but after running it up to 7k rpms a few times, it finally quit and i havent had any issues since.

 

That is weird...

If it was just from going hard off the line I would say that it was DSC / TSC kicking in, but 15 mins? Dang.

 

I think its a troll. Where do you get gas with that Octane?

 

He's in Cyprus and they probably use a different octane rating system. Or, less likely, they actually have that level of octane which we obviously do not.

 

correct, here we have european rating 95, 98, 100 octane.

Both times this happened it was within 24hrs of changing something (1st time when i swiched fuel to cheap 95) this time when i changed all the oil (except filter) to 10w40 semi-syn so maybe its the ecu re-callibrating itself.....actually that sounds a bit far fetched

 

Check the air filter for oil. The only time I had the power loss (and a CEL for 15 seconds) was when ~100 mL of motor oil got into the air intake. Oh, the mess I had to clean..............

 

I suppose that the 100 octane is not unleaded. correct me if i am wrong.

Lead will destroy your catalytic converter. On my previous VW golf my mum used to put super gas (with lead) [women :P] and she completed destroy the catalytic converter. As a result the car had a 70% loss of power.

 

only Eco stations do 100 octane unleaded in Cyprus

 

I believe minty refers to RON used by those familiar with the metric system. I could be wrong. US i believe use MON???? I am only familiar with RON... I think from memory 95 RON = 91 MON, 98 RON = 93 MON.... Correct me if I am wrong.