SP767

It seems to me that my stability control has stopped functioning.

I have 7k miles and 5 months ownership on my car. In the first few thousand miles, it felt that i could not unstick the car. I could feel the car braking and even reducing power in those situations.

Now, I cannot feel the DSC kick in. My car is slipping on wet pavement. I haven't tried to be aggressive enough to see if i can spin the car.

So, my question is, how do i know when the system is working?

And what is the difference between traction control and dsc? Is there an idiot light for each?

steve

jtimbck2

Your tires aren't new anymore. These performance tires are very sticky, and very soft. They wear very quickly. That's why it's slipping on wet pavement.

SP767

OH, i forgot to say in my initial thread that i bought and installed new Conti extreme contact high performance all seasons on my car last month.

steve

rx8cited

Did you notice the lack of DSC/TCS before or after the new tires?

rx8cited

StewC625

Here's how to test it:

1) With the DSC on, and on wet pavement, preferably asphalt/tarmac rather than concrete (slicker), rev the engine to 4000 rpm, dump the clutch and floor it in 1st gear - you will get wheel spin and the DSC light should flash and the system should arrest the wheelspin.

2) With the DSC on, in a LARGE parking lot, again preferably asphalt, and ideally in the rain, drive in a large circle (making sure that if you DO spin out, there is nothing to hit and no major cracks or storm drains to slide across), smoothly gaining speed until you feel the system working - you should feel jerks in the steering wheel and the seat as the system applies individual brakes to keep the car in line.

Let us know how these tests work out. It's very key to do this, not just to verify that it works but to also learn how the system performs.

Stew

SP767

Okay, i will try this experiment.

i have noticed this after i got my new tires.

steve

rx8cited

Mmmm, so I wonder if it's not the new tires then?

I'd hope the TCS/DSC systems have diagnostics that run and would give a fault indication if not working.

Let us know the results of your experiment.

rx8cited

StewC625

FYI - I learned these tests at BMW's M5 Driving Experience school at the Spartansburg, SC facility. A buddy of mine bought an M5 and this school came with it ... that's how they taught us how to trust the DSC in the M5.

zevans

Basic law of troubleshooting is... if it broke, find out what changed. This has GOT to be related to your new tyres.

Maybe the new tyres are just not any good?

BTW I agree with what the other poster said - the Bridgestones seem to have got a lot worse since about 5000 miles.

StewC625

By the way, the stability control won't save your *** if you do something truly stupid. I was driving my buddy's M3 last week in New York in the rain, took a corner WAY too hot, and got completely sideways - the DSC was working furiously, and probably saved my butt from an "off" (as they call going off the road in Formula 1 ... as opposed to a "shunt" which is a collision).

iridearocket

Hammer the gas in first gear with the steering cranked around and you'll find out if the tracktion control is working. Try this trick in a parking lot well away from lamp posts. Sounds funny... but you would have had your answer within 3 seconds flat... rather than writing about it.

StewC625

Yeah, but that doens't teach you how the system will react and exactly WHAT you can get away with before you over-extend "the nanny"'s capabiliy to save your butt.

HeelnToe

I can definately step the rear end out in wet weather if I feed in throttle too early in a corner. It's never spun of course, but it definately steps out sideways a bit. I then reflexively ease off the gas, so I dunno if it's TCS or my foot that brings it back.

I also get plenty of wheelspin when starting out on wet hills.

I haven't had the guts to just drop the clutch and see when/if it arrests the slipping... nor have I looked for the warning light (I'm kinda busy at the time, lol).

Makes me wonder though how much help it's going to be in the snow. Being a sports car, it is nice that it stays out of the way in dry weather. But I wish it was MORE intrusive in slippery conditions.

zevans

TCS isn't designed to help out in snowy conditions. In snow, there's no substitute for snow-style driving. Since the 8 is low torque at low revs it's pretty easy to handle on gravel with TCS off - haven't tried it on snow yet I confess.