Hello ,

After tyre replacement and wheel alignment my Panda goes straight but if I keep the steering wheel straight it goes to left ! From 2 wheel shops the wheel alignment machine shows that the car is perfect. I noticed that the steering wheel doesn't have "tooth" when you remove it and re-install it. If I loose the nut and alignment 1mm with the hand I will make problem with the sensor or not ?

As far as I remember, wheel only fits on one place, column to rack only in one place, so has to be right.
Despite alignment being right, it appears that they have adjusted one side only at the rack. Whilst this will show as straight, it will change the angles the wheels turn, so will be incorrect as it turns. This will cause tyre wear and poor handling. Side rods at rack need to be equal length.

portland_bill said:

As far as I remember, wheel only fits on one place, column to rack only in one place, so has to be right.
Despite alignment being right, it appears that they have adjusted one side only at the rack. Whilst this will show as straight, it will change the angles the wheels turn, so will be incorrect as it turns. This will cause tyre wear and poor handling. Side rods at rack need to be equal length.

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So the steering wheel is fiting one place. The angle sensor needs calibration or not ? Is it possible to loose his "calibration" ?

The tracking job was messed up.

Set the steering wheel straight ahead centre, then adjust the track rod ends to get both wheels pointing ahead. One will need to be moved out the other moved inwards.

Unless the garage/tyre shop has a full four wheel computerised laser setup that also accounts for out of true wheels then I won't use them, or I'll do the tracking myself.

Decent makes of kit like Hunter will give accurate measurements of toe, caster, camber and importantly "setback" and "thrust angle". These latter two can seriously affect the correct setting of the correct toe (left and right) to get a straight line level steering wheel drive.

If I do it myself then I can't easily measure setback and thrust angle. Instead one has to set the toe knowing the steering wheel will not be level. Than got for a drive on a perfect flat sure (e.g. open car park) or drive on the crown of a straight road (while line up the middle off the car) and note the steering position. Return to base and adjust BOTH side accordingly and repeat test drive. May take three of more goes to get it all OK. Not the quickest of jobs but you soon learn which wheel and direction to adjust first and follow up with the other.

I read the original post as the car is tracking perfectly but the steering wheel isn't centred

Personally I would leave it alone.

koalar said:

I read the original post as the car is tracking perfectly but the steering wheel isn't centred

Personally I would leave it alone.

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The tracking can be perfect in geometry terms but if when it's set with steering wheel not centred you will have PAS problems. The garage should know better and do the job properly.

DaveMcT said:

The tracking can be perfect in geometry terms but if when it's set with steering wheel not centred you will have PAS problems. The garage should know better and do the job properly.

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The PAS will give me problem with wrong alignment?

There is a mid point where the PAS is not activated. Steer to either side and torque sensors will apply electric assistance. The tracking needs to be done again with the steering wheel correctly centered.

There is another reason to get it done. At the moment you have a maximum under steer to one side and an over steer to the other side. That could cause the over steering tyre at full lock to foul on bodywork or some such. It may be fine but (very) not good if that is happening.

Tomorrow I will go to garage and make calibration to sensor and after that check to front axle. After that again alignment the car. Its stupid problem that causes headache to engineers but my car was perfect at street. So I want to be perfect again

It's easily done and quite common, but it's not been aligned properly.
The track has been adjusted with the rack not quite centered.

The steering rack needs to be centered properly, so there is equal amounts either end.

If nothing has been apart, this should be when the steering wheel is straight and the column/torque sensor in the middle.

I keep up to date the process these days

FFS stop thinking about calibrating the PAS. This is nothing to do with the PAS and is entirely an alignment problem. The PAS is only responding to the incorrect alignment. If you recalibrate the PAS you are creating another wrong. In the UK we have a saying, "Two wrongs do not make a right".

You need to fix the fault, not the result.

My engine is running rich (too much petrol). No worries, I'll drill a hole to let more air in. The "solution" solves one problem but creates many more. Dear Fiat Forum where should I drill that hole to solve my engine problem?

Clearly the above is a silly example but it should illustrate what we mean.

Get the wheel tracking done properly and your steering will be fine.

DaveMcT said:

Dear Fiat Forum where should I drill that hole to solve my engine problem?

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In your/the head

s130 said:

In your/the head

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As I'm sure you guessed it was a flippant comment to illustrate the point about a bodged fix leading to even more trouble.

I pick up the car today ... and the result are that the wheel is at zero position . But the two Engine Mount front left and transmition were off tottaly. The xar goes much at street . These days I will go for a wheel alignment .

UPDATE :

The car had new alligment settings. From measurements the front right absorber has 1mm deviation from factory and was creating the problem pulling the car to left with the wheel at zero position. So we make new settings and the car goes absolutely straight again !