Hello!

I have a problem with my Uno Mia 1100.
When I drive low or fast (100km) speed, the car suddenly spasms to the left for a few seconds, and then returns to normal by itself, A minute or five later, it would happen again and occurs around bends or straights.

It is like the car cramps up and throws to the left momentarily (the steering actually swerves, and I have to keep my hands firmly on the steering wheel), staying in this cramped up state for a few seconds, then it "relaxes" and recovers by itself to normal. It is quite unnerving.

It makes you feel like driving on semi-flat tyres for a few seconds, drifting to the side, before it recovers.

My tyre inflation is correct.

This is very dangerous and need to be fixed but I don't know what to check first. Can anyone advise please?

Thanks you.

I had this in a StreetKA. Ball joint rubber bushing had completely disintegrated.

Do you get loud bangs as you drive over potholes and bumps, metal on metal?

A good idea to check all the suspension and steering joints and bushes.

Then check the brakes. Fronts have a tendency to get tight due to dust and corrosion, and regularly need the caliper mountings cleaned to allow free movement. Rear brakes need to be checked too. The linings wear slowly, but on small Fiats, the glue that holds the lining to the shoe can let go with age. The loose lining can seize a wheel. Momentarily holding and letting go is an early warning. Surprisingly, a single rear wheel gripping will throw the car off line quite fiercely.

If those checks bring no fix, the problem might get more serious.
Does it have ABS? These systems are very reliable, but can play up. If it applies a brake, you'll get the result you describe. Does the ABS light show when the problem occurs? (The dash lights are not where you tend to look when the car heads for the ditch.)
There have been issues with early Puntos, with the differential pin breaking or becoming insecure. This is inside the gearbox, difficult to diagnose, and expensive to fix, but catastrophic if it fails completely. It could be trying to escape and trying to lock one wheel. Draining the gearbox oil into a clean container might reveal nasty metal bits, or hopefully not. Late Uno gearbox likely to be same or similar to early Punto.

Good luck, needs to be diagnosed before it ends in tears.

Thanks for the replies.

I went for a short drive today and it is still there. I don't think it could be the brakes because the car would slow down, which it doesn't. So it must be something else.


I did change the right cv joint boot he other day as well as the right tie rod rubbers but the problem literally only started the day before. I will give it a check sometimes this week. Just cant figure out why it recovers on its own though.



Could it be wheel alignment?

Do ypou have EPS on the car? If you do, the problem could come from there, it does that when the torque sensore is gone.

Unfortunately no EPS in car, normal rack n pinion steering.

I advice you, next time the car makes like that, to pull over, jack up the left wheel and try to figure out where the problem is, spin the wheel, feel and listen.
My guess is that the wheel's bearing is broken.

Thanks. I might have to try that. I do hear clacking sounds and noises in the front when I turn (quiet in straight) but can't figure out what it is. (It's not cv joint). Is a bearing expensive and hard to replace?

Expensive it is not. Hard to replace... Yes! Very much so!
Here's a video for the Punto, I'm guessing there are not many differences to Uno:
https://m.youtube.com/watch?v=jF_7RRQ0Ssg
And there is the possibility that the bearing to be broken and is very hard to get it out or it might even break the spindle. But you have to replace them if they need replacement, hope everything goes smooth when you replace them. I used the plural in case they need to be replaced on both front wheels. If you don't have the tools it's best to go to a service for this job.

A wheel bearing should be pretty noisy, more a rumble. However, not too difficult to check.

Jack the left side and spin the wheel as said before, if nothing is obviously wrong do the same on the right side to compare.

You said “Clacking”, is that metal clanking against metal? A failed bushing would give you that type of sound.

Yes clacking sound when I turn, not very loud but audible with window down. I dont hear anything else when Im driving straight. Hopeully I can have time tomorrow to get a quick check. But I am rather worried. I don't use the car much, maybe once every two\three weeks for quick town trips. Maybe that's bad.
Ill try and make a video.

If you replaced CV boot I assume that you removed the drive shaft? If so then you would have had to split the hub assembly from the suspension strut?

Your problem *may* be with the two strut to hub bolts not done up tightly enough. There is a degree of play (bolt to 4 hole clearance tolerances) that when the bolts are lose then the hub assembly can move up and down. This in turn will change the effective angle of the steering arm and steering rod length and thus the hub/wheel steering angle.

When ever I have split the hub to strut interface on reassembly I always preload the hub to the up position before tightening the bolts and then check the tracking.

Certainly worth checking those bolts for tightness because even if the hub is not flopping around it can change position due to cornering loads, bumps in road, etc.

s130 said:

If you replaced CV boot I assume that you removed the drive shaft? If so then you would have had to split the hub assembly from the suspension strut?

Your problem *may* be with the two strut to hub bolts not done up tightly enough. There is a degree of play (bolt to 4 hole clearance tolerances) that when the bolts are lose then the hub assembly can move up and down. This in turn will change the effective angle of the steering arm and steering rod length and thus the hub/wheel steering angle.

When ever I have split the hub to strut interface on reassembly I always preload the hub to the up position before tightening the bolts and then check the tracking.

Certainly worth checking those bolts for tightness because even if the hub is not flopping around it can change position due to cornering loads, bumps in road, etc.

Click to expand...

Following on from this, there are risks of the driveshaft notbeing fully clicked into the diff, the shaft circlip being 'lost' in the diff, or the hub nut not being tight enough.
The whole lot needs careful checking, before the vehicle is driven again. Continuing to drive in this state may result in a nasty situation.

[SOLVED] Re: Dangerous jerk to left

[SOLVED]

Ok an update. I think the problem is solved. Thank you for everyone's pointers.


Under the car I saw the right ball joint nut almost completely loose. one or two more turns and it would have come off completely! To properly tighten it I had to take off the wheel and slide out cy joint-drive shaft. I inspected that and saw nothing wrong or bad (with my limited knowledge), although the cv joint circlip was a bit loose. There is a bit of in-out play on the drive shaft from the engine case but that's ok I assume. At least the drive shaft\cv joint can't fall out because of the wheel nuts. So the ball joint nut is tightened properly.

Then I also checked the brake pads. The right front pad were almost crumbs. The whole pad had broken up and just the caliper itself was keeping the pad crumbs in place. Replaced with a spare pair.

Took it for a ride and there was a nasty clacking\knocking sound coming from the engine but it soon went away confused. So far everything feels 99% good. I think I still do feel a very sliiiiight slide still happening but overall Im good.

I don't know what "fixed" it between the ball joint nut, drive shaft\cv joint and brakes but if this hair raising thing ever happens again, that's where I'll go first.

Thanks for the advice guys!

Well I'm certainly not going to criticise you as I have in the long past done a job to tackle and issue and focussed on that only later to realise there were multiple issues. That was many years ago when I first got into vehicle maintenance and then subsequently learnt that the obvious is obvious but the minor issues can be more troublesome etc. than the one that caught your attention.

Hope all is well now.