Hello all,
again a question to the old fulvia drivers : is there an effect on the steering under "heavy/normal" accelerations (to the left) and quick releasing of the pedal (to the right).
the fact is i do have this on mine...? I just discovered it as i am learning how to use this new little car on the roads.
like on a good old bmw on two wheels.
The only explanation i can find is the engine position, but i may be wrong, with somehting bad in the front system...
Thanks again for your attention,
Thibaut
torque effects on steering under acceleration
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Huib Geurink
Re: torque effects on steering under acceleration
It is called torque steering.
Suspension ball joints, steering ball joints and other steering parts all have a little play. If they would not have any play, they would not move, swivel nor turn. The play is or at least should be very minimal and as long as the total cumulative play on left and right are equal there is no problem. Íf everything is all right you would not even be able to feel any play by hand. However if a few dozen horses are pulling the 1000+ kilograms of your car the situation is different.
If the front wheels are pulling the car (when you put your right foot down), they tend to move toe in. If the car is pushing the front wheels (when you lift your foot), they tend to move toe out. If you lift your right foot and have more play on one side, that wheel goes more toe out and the car steers to that direction. Since the play has to be measured with respect to the steering box chances are that the car pulls to the passenger side when you lift your foot as there are two more track rod ends (those of the central tracking rod) on that side. If you put your foot down , the opposite happens.
Also, in the UK left turns are sharper. On the continent right turns are sharper. There is more movement on the track rod ends on the passenger side. (The front tire at the passenger side wears more and has statistically more flats)
Usually one of the track rod ends has gone bad.
Other possible causes are play in the idler box or bad bushes of the lower wishbones. Bushes of the upper wishbone hardly go bad.
Play on the upper suspension ball joints is under normal conditions eliminated by the weight of the car unless the plastic inside has completely worn out or is broken.
There might be some play on the lower suspension ball joints. If you have De Carbon shocks some of the weight of the car is transferred to the lower wishbones which helps to eliminate play on the lower suspenion ball joints.
I assume all nuts and bolts of the suspension and steering have been properly torqued.
Suspension ball joints, steering ball joints and other steering parts all have a little play. If they would not have any play, they would not move, swivel nor turn. The play is or at least should be very minimal and as long as the total cumulative play on left and right are equal there is no problem. Íf everything is all right you would not even be able to feel any play by hand. However if a few dozen horses are pulling the 1000+ kilograms of your car the situation is different.
If the front wheels are pulling the car (when you put your right foot down), they tend to move toe in. If the car is pushing the front wheels (when you lift your foot), they tend to move toe out. If you lift your right foot and have more play on one side, that wheel goes more toe out and the car steers to that direction. Since the play has to be measured with respect to the steering box chances are that the car pulls to the passenger side when you lift your foot as there are two more track rod ends (those of the central tracking rod) on that side. If you put your foot down , the opposite happens.
Also, in the UK left turns are sharper. On the continent right turns are sharper. There is more movement on the track rod ends on the passenger side. (The front tire at the passenger side wears more and has statistically more flats)
Usually one of the track rod ends has gone bad.
Other possible causes are play in the idler box or bad bushes of the lower wishbones. Bushes of the upper wishbone hardly go bad.
Play on the upper suspension ball joints is under normal conditions eliminated by the weight of the car unless the plastic inside has completely worn out or is broken.
There might be some play on the lower suspension ball joints. If you have De Carbon shocks some of the weight of the car is transferred to the lower wishbones which helps to eliminate play on the lower suspenion ball joints.
I assume all nuts and bolts of the suspension and steering have been properly torqued.
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Randy Adams
Re: torque effects on steering under acceleration
I agree with Huib. Most likely it is the tie rod ends. Once they start to go bad, they get worse fairly quickly. They are easy to replace. I doubt the ball joints will be the cause. If the ball joints are bad, you will probably experience an alarming non-linear steering response when you make small adjustments at the wheel.
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Paul de R. Leclercq
Re: torque effects on steering under acceleration
Yes agreed.
With Series 2 and 3 cars, the usual culprit is the idler box.
The reason for this is that the S2 & 3 track rod ends were superior to the S1 ones - being about 50% bigger - they hardly ever fail - whilst the idler box was vastly inferior, having pathetic nylon bushes instead of the lovely bronze ones of the S1.
We frequently have to overhaul these. Rather than buying and inserting bushes (assuming that the shaft is not hopelessly corroded) we make bushes, insert them and line bore in situ. This procedure usually works!
Paul
With Series 2 and 3 cars, the usual culprit is the idler box.
The reason for this is that the S2 & 3 track rod ends were superior to the S1 ones - being about 50% bigger - they hardly ever fail - whilst the idler box was vastly inferior, having pathetic nylon bushes instead of the lovely bronze ones of the S1.
We frequently have to overhaul these. Rather than buying and inserting bushes (assuming that the shaft is not hopelessly corroded) we make bushes, insert them and line bore in situ. This procedure usually works!
Paul