Technical Front strut, alignment ....questions?

[Aad Doix]

Hi Forum,

Back after a while enjoying my car and some questions I can;t figure out myself due to lack of technical knowledge.

A few weeks ago I had a little accident where I was braking while driving onto a curb to dodge a biker. To be sure nothing really was damaged I brought the car to the garage for a checkup, alignment and balancing the front wheels. It also needed a new MOT.
The issue I now face is that the car got a new MOT, but after alignment the steering wheel is a bit off to the left. I contacted the garage with the question whether this could be solved, but they mentioned:

" But it's true that the car still pulls slightly to the left, and that's probably due to a bent shock absorber strut, right? That impact against the front wheel also bent the strut, didn't it? This can, of course, be fixed with a new strut. "

It passed the MOT, but this message gives me slightly the shivers so to say. So, is there a way that I can check what is possibly bent and if yes, what to look for? And if replacement is needed, do changing front absorber struts going by the pair or is, in general use, replacing only the damaged one the way to go?

Thanks a lot for your reply and kind regards,

Aad

 

[bugsymike]

Hi Forum,

Back after a while enjoying my car and some questions I can;t figure out myself due to lack of technical knowledge.

A few weeks ago I had a little accident where I was braking while driving onto a curb to dodge a biker. To be sure nothing really was damaged I brought the car to the garage for a checkup, alignment and balancing the front wheels. It also needed a new MOT.
The issue I now face is that the car got a new MOT, but after alignment the steering wheel is a bit off to the left. I contacted the garage with the question whether this could be solved, but they mentioned:

" But it's true that the car still pulls slightly to the left, and that's probably due to a bent shock absorber strut, right? That impact against the front wheel also bent the strut, didn't it? This can, of course, be fixed with a new strut. "

It passed the MOT, but this message gives me slightly the shivers so to say. So, is there a way that I can check what is possibly bent and if yes, what to look for? And if replacement is needed, do changing front absorber struts going by the pair or is, in general use, replacing only the damaged one the way to go?

Thanks a lot for your reply and kind regards,

Aad

If the garage simply checked the wheel alignment and then adjusted the track rod end on the side that took the impact that would account for the steering wheel being out of position. But as you have found, it doesn't fix the pulling to one side.
Whilst it is possible the suspension strut has been damaged, it is more likely that the steering track rod end or the arm coming out of the steering rack is bent.
It can even be the lower wishbone bent or where it mounts to the sub frame , so it does need close inspection.
Depending on angle the car took the impact would affect which steering or suspension part took the damage.
It doesn't sound like your garage did very much inspection work.
The most important point is what was damaged in the initial impact which should then have been replaced before any wheel alignment is done.
What it needs is an experienced mechanic to have a close look at the the suspension both sides to compare the damaged side with the good one.
As an extreme case years ago we had a customer with a Fiat Strada that hit a hidden storm drain cover and after inspection the car was written off!
The clue was it had caused the body to deform and put a dent in the roof panel, I repeat that was an extreme case.
The most likely cause in your case if only a moderate impact is a steering arm bent.
In answer to your last question whilst it is good practice to fit shock absorbers in pairs, providing the undamaged one is in good working order there is no reason why you cannot just fit a single one.

 

[Aad Doix]

BugsyMike,

Thanks for the quick reply.
I have no idea which side took the first impact. Or does the side the car is pulling to a clue in this? It does drive normal, no vibrations, only the steering wheel is a bit to the left ...

 

[bugsymike]

BugsyMike,

Thanks for the quick reply.
I have no idea which side took the first impact. Or does the side the car is pulling to a clue in this? It does drive normal, no vibrations, only the steering wheel is a bit to the left ...

Sorry from your original statement I assumed only one kerb/wheel impact.
However generally the side it pulls towards is most likely to be the damaged side.
To confirm it really needs a good mechanic to have a close inspection, often involving the car to be put on a ramp and even take the wheels off to check further.
If the car is still pulling to one side then there has to be some damage that hasn't been corrected by adjusting the wheel alignment.
As the car was driving correctly/not pulling to one side and the steering wheel was straight before the impact, then all the wheel alignment has possibly done is adjusted the wheels so they both point in the correct direction of "toe in or toe out" according to manufactures specification.
If the damaged parts had been replaced then normally a minimum adjustment of the tracking/wheel alignment would have been sufficient.
If all the suspension and steering parts are in good order then when tracking/alignment has been done both track rod end threads should be equal length showing against the lock nuts.
I have seen examples where a car pulls to one side due to a poor fitter simply adjusting one side and so due to the unequal length of track rod end that can cause a car to pull to one side.
However not in your case as the fault occurred after the impact, so simply adjusting the wheel alignment without replacing the damaged parts is the wrong thing to do.
Proper inspection is critical, many years ago we had to collect a car that had been parked correctly, but a drunk driver had driven down the side of several cars. The body work and damaged wheel and tyre were fixed but steering wheel was found to be out of line. Looking underneath the car there was nothing obviously wrong, but on stripping the steering box (it was a nearly new Mazda but had a steering box rather than a steering rack like modern cars) we found the spline coming out of the steering box had a twist in it which could have proved fatal if it had sheared. The photo below shows the spline on the right hand side that was damaged where the nut is.
The point I am making is the damage where ever it is, needs to be fixed before any adjustment.

 

[puntodad19]

How was the wheel and tyre ?

Your not sure which side hit the curb first, meaning both sides mounted the curb ??

Car drives normally but pulls to one side ???

If it pulls to one side something is wrong.

Castor, camber, kpi and a full alignment check...and s more in depth visual check of whole front end, rear end as well.

Biker, pedal bike or motorcycle ?

MOT tests although more thorough these days are still a bit of a joke imho.

 

[bugsymike]

MOT tests although more thorough these days are still a bit of a joke imho.

I agree, speaking as someone who used to be an MOT tester whilst foreman of a Dealership in the 1980s, I have found an MOT is only as good as the tester doing the job and have seen many examples of stuff being missed, even today though I am long retired.

 

[koalar]

Did it track straight before the impact
Did it alter after the impact
Did it alter after the alignment

but after alignment the steering wheel is a bit off to the left. I

Is the steering wheel now not pointing straight after the alignment

 

[Mike1alike]

Steering pulling to the left can be caused by faulty EPS, too, more precisely faulty steering angle sensor inside steering column. And that sensor can totally get damaged on impact.
So if physically they can't find anything wrong with the car, it can be the EPS causing it. Simple check would be to unplug the EPS module's plugs and see how it drives, if it still pulls one side.

 

[bugsymike]

I have very little experience re EPS.
In the past with hydraulic power steering if I suspected a fault in that direction I used to find a quiet hill, switch the engine off with ignition on (steering lock can make life interesting) and free wheel down the road, if vehicle stops pulling to one side then fault is in the power steering side.
If car crashes then steering lock is still on. Yet another case of don't try this at home folks.

 

[Aad Doix]

I see that I described some things a bit unclear, but English is not my native language. I will try to clear things up:

The car was aligned after replacing the front arms and strut bars last October. The steering wheel was straight since then. Two weeks ago when leaving a roundabout at night suddenly a bike (normal bike, no fat-bike, no motorbike, no electric one) appeared in front of me. To dodge the bike I choose the central curbs between the two lanes (one lane off which I was on and one lane for oncoming traffic) and entered those when braking. I have no memory which front wheel hit the curbs first or that both hit it simultaneously. Unfortunately I also hit the bike and also hit a lamppost which was placed on that central curbs, but almost no damage to front bumper and no airbag went off. The most important thing though, is that the cyclist fortunately suffered little and was able to return home on his own after being checked in an ambulance.

After this incident I saw that the steering wheel was a tiny little bit of to the left and above 75 mph little vibration was felt, so next to the MOT I thought it wise to do alignment and balancing front wheels, just to be sure. I never thought or asked about checking the front suspension because the car was feeling okay still.

But now the car is aligned, the steering wheel is a little bit more off to the left than just after the incident (around 5 degrees in comparison to a straight horizontal line when driving straight forward), which means that when I have the wheel straight, the car will slowly go the the right side of the road. There are no vibrations anymore.

But okay, when having time this weekend I will first check myself the front suspension and will ask the garage or a second one to check next week.

P.S. I read above something like unplugging the EPS? Is that possible? And could something like this be done permanently?

 

[koalar]

The easiest way is to pull the fuse, But there is no need, the EPS will not be effected by the impact

Unfortunately the alignment hasn't been done equally, steering wheel has altered

This will be effecting the self centering which is done electronically

The steering wheel has to remain at the same position before and after the alignment, otherwise the EPS calibration has to be redone, can be done in MES among others

Check also the tyre pressures,

 

[Mike1alike]

Yes, after you said all that it doesn’t sound at all as an EPS problem.
Sonds just like they didn't align the steering wheel properly.
Doesn't sound like suspension problem either.

 

[bugsymike]

As you found the steering to be out of align at the steering wheel following the accident this would indicate something has been damaged, so, I would explain about the accident to a garage you trust, ask them to check the steering and suspension for damage and once they are satisfied no further damage or you have had it repaired then have the steering aligned preferable with both track rod ends equal length.
Then as advised by @koalar the EPS may need to be recalibrated.

 

[Aad Doix]

What exactly does such an EPS calibration entail? And what happened when it is not done?

 

[koalar]

Tells the EPS where 0 degrees now is

 

[The Panda Nut]

My Panda 100 had this exact issue when I bought it. A proper garage readjusted the tracking correctly with the steering wheel centred as it should be and then correcting both track rods instead of one, and it was fixed.

 

[koalar]

My Panda 100 had this exact issue when I bought it. A proper garage readjusted the tracking correctly with the steering wheel centred as it should be and then correcting both trck rods instead of one, and it was fixed.

If your handy you can do it yourself via trial and error

Mark each side with a center punch, turn one side in and the other side out exactly one turn,

As long as whatever you do to one side you do the opposite to the other the tracking stays the same

 

[koalar]

As far as I know the only way to test for a bent strut is off the car

Spin the shaft and watch the end wobble

However is it's not obvious visually or leaking, they are normally okay

Worn struts should be changed as a pair

 

[Pugglt Auld Jock]

My Panda 100 had this exact issue when I bought it. A proper garage readjusted the tracking correctly with the steering wheel centred as it should be and then correcting both trck rods instead of one, and it was fixed.

That's the way to do it. The power steering is calibrated in the straight ahead steering wheel position. So, when adjusting the track rod ends you need to end up with the steering wheel in the straight ahead position and equal toe on both front wheels whether there is damage to some component in the suspension/steering/whatever. If the wheel is not straight ahead when driving straight ahead it's probably not been adjusted by someone who knows what he/she is doing and there may, or may not, be damage to something. With electric power steering though, if the wheel isn't straight the electric rack may well be trying to centre the wheel as it thinks this is straight ahead.

As Mike said above, the starting point for any adjustment of suspension/steering is a thorough and very detailed inspection of all components and chassis mounting points. If any defect at all is found then attempting an adjustment without rectification is a total waste of the customers money and most unlikely to end satisfactorily. I believe some of the newer computerised laser wheel alignment benches run a check for worn components before starting. They are very expensive so that's something the average garage, maybe even main dealer, will be unlikely to have. As an operator, having done many hundreds, maybe thousands, of toe adjustments in my time, I would say that one of the classic symptoms of wear in steering/suspension is that you end up "chasing" a setting. By that I mean that you measure the existing angles and carry out the adjustment, maybe run the vehicle back and forward a couple of times and when rechecked you find the angle has changed. So you repeat, taking greater care to set the angle up "perfectly" but after moving the vehicle and rechecking, you find it's changed again. It does this because there's wear in a ball joint or bushing or possibly even a broken part, so each time you move it the wear allows the component parts to move in relation to one another. In particular rubber bushes which have softened or cracked can be quite difficult to find sometimes. Wear in ball joints or cracks in something like a suspension arm are easier to see.

 

[The Panda Nut]

That's the way to do it. The power steering is calibrated in the straight ahead steering wheel position. So, when adjusting the track rod ends you need to end up with the steering wheel in the straight ahead position and equal toe on both front wheels whether there is damage to some component in the suspension/steering/whatever. If the wheel is not straight ahead when driving straight ahead it's probably not been adjusted by someone who knows what he/she is doing and there may, or may not, be damage to something. With electric power steering though, if the wheel isn't straight the electric rack may well be trying to centre the wheel as it thinks this is straight ahead.

As Mike said above, the starting point for any adjustment of suspension/steering is a thorough and very detailed inspection of all components and chassis mounting points. If any defect at all is found then attempting an adjustment without rectification is a total waste of the customers money and most unlikely to end satisfactorily. I believe some of the newer computerised laser wheel alignment benches run a check for worn components before starting. They are very expensive so that's something the average garage, maybe even main dealer, will be unlikely to have. As an operator, having done many hundreds, maybe thousands, of toe adjustments in my time, I would say that one of the classic symptoms of wear in steering/suspension is that you end up "chasing" a setting. By that I mean that you measure the existing angles and carry out the adjustment, maybe run the vehicle back and forward a couple of times and when rechecked you find the angle has changed. So you repeat, taking greater care to set the angle up "perfectly" but after moving the vehicle and rechecking, you find it's changed again. It does this because there's wear in a ball joint or bushing or possibly even a broken part, so each time you move it the wear allows the component parts to move in relation to one another. In particular rubber bushes which have softened or cracked can be quite difficult to find sometimes. Wear in ball joints or cracks in something like a suspension arm are easier to see.

Ive been going to our local Tyre Pros. The manager knows his stuff and I like the repeater screens in the waiting area so you can see what they are up to. They have done all the cars for over ten years and tyre wear has been normal excepting when a component has failed. Many years back the manager said the equipment in each bay cost over £100K. WHatever so fa tits worked reliably and has saved its costs Im pretty sure.