Bad service at garage - engine coolant

bigjl

droopsnoot wrote: »

That's not the case on a car with ESP, or other electronic stability systems, and I don't know whether the OPs car has such a system. ESP compares the physical direction of the vehicle (obtained from lateral and longitudinal acceleration sensors) to the steering angle (from the steering angle sensor) to establish whether the car is oversteering or understeering and attempts to correct issues if it finds them. Drive an ESP-equipped car with the steering more than a very small number of degrees out and you'll see that the ESP keeps trying to correct a problem that isn't there.


Correct that it doesn't mean the tracking is wrong, but having the steering wheel at an angle isn't always irrelevant.

I can't see a slightly misaligned steering wheel making any difference to the steering angle sensor.

The sensor looks at the amount of turning of the wheel surely? My Picanto has a steering angle sensor, if you park with the wheels not straight ahead it warns you of the fact the you next start the car.

When bought the geometry was slightly out and the steering wheel not perfectly centred.

Had the geometry done, wheel is now perfectly centred.

Surely the software will be able to tell the difference between a slight steering misalignment and over steer or understeer.

droopsnoot

Yes, I was just trying to clarify that it's not strictly correct to call it irrelevant - it used to be just an annoyance, but it isn't necessarily any more. I did say "more than a very small number of degrees", though I recall looking for a better way to phrase it because, like the toe-in, the tolerance might be much smaller than a "few degrees".


But no, I don't imagine the software can tell the difference between a slight steering misalignment and oversteer or understeer. After all, the angle of the steering wheel compared to the physical direction the car is travelling is how it decides whether you are in either condition, and I can't think how it would know the difference.


For a very small tolerance it probably won't matter, but it doesn't take much of a change in the toe-in to cause enough of an angle to be noticeable. As Edgasket said though, probably not relevant for the OPs car, though Google (well, the C3 owners forum) suggests that at least some C3s have one - don't know whether that's for ESP or for the warning that bigjl mentioned (which I hadn't heard of before).