Zero1789

I posted this issue in the CLS section but unfortunately didn't get any replies. I know the W218 is based on the W212 so maybe someone here could shed some light on this instead. I would be incredibly grateful.

My tie rods were replaced recently and since then my steering has had a pull to the right after alignment (report attached).

. The pull gets steadily better the faster you go. At low speeds, like less than 5 mph, the steering wheel actually turns itself from dead centre to about 10 degrees to the right.

I know this car has electric steering and I've used a good quality code reader but there are no codes active or stored. Any suggestions would be really appreciated!

konigstiger

Check with: https://mbworld.org/forums/e-class-w...ml#post7278657

Zero1789

Thanks konigstiger. I understand camber and caster adjustments may be necessary to properly align this vehicle and I might need camber/caster bolts to do this. But as from the report above, I didn't think the alignment was that out of spex to produce this kind of strong pull.

Additionally, the steering is heavier turning left and lighter turning right. My issue is I'm trying to figure out if this is a problem with the electric steering rack or just an alignment issue? How can I do that to properly diagnose it?

konigstiger

Have someone erase all stored codes and do a quick test using Xentry (MB diagnostics) to pull current code(s).

Senecat

Well, the big red boxes are indicating that your right side camber is horribly out of spec.. I would start there maybe?

S-Prihadi

Something is wrong with that alignment machine, why there is no front CASTER data ?
I would not trust an alignment shop result like that.

Also there should be BEFORE and AFTER to see the adjustment/correction made where applicable, like TOE.
Go to this page, post #49 and filter the data suitable for your car model and option and use it as the reference.
https://mbworld.org/forums/e-class-w...ml#post8651095

This is a good alignment 101
https://mbworld.org/forums/e-class-w...ub-radius.html

Good luck

DFWdude

Tie rod ends are replaced WITHOUT an alignment? Take it back to the shop and have them fix it.

Zero1789

The tie rods were replaced and then alignment was done. The alignment shop couldn't do caster angle because their Hunter machine didn't support it. The car actually tracks dead straight when the steering is held straight. It's just it has a tendency to turn right at very low speed less than 5 mph.

I've even jacked the front up to try and exclude a geometry issue. The actual steering feels a little bit heavier turning left and lighter turning right which is why I was thinking this isn't an alignment issue. But there are no trouble codes relating to either the electric steering module or steering column module, hence I'm left scratching my head.

I guess I will start with another alignment and maybe go to the dealer who can correct all geometry aspects using bolts but it will be pricey!

SteveE400

Both front and rear camber on the right side are overly negative. Was the car ever damaged?

Sliding it into a curb could damage suspension components such as control arms or bushings, which could eventually result in mis-alignment and pulling. I think you need to bring it to a shop that is very familiar with Mercedes suspension to diagnose the damage. A "generic" alignment shop will have neither the skills nor the experience to properly resolve this issue.

cetialpha5

Right, I was going to guess worn suspension items throwing off the alignment. The solution is to replace the worn parts, not correct for the worn parts.

Left Coast Geek

I remember very specifically, my older 1990 vintage Mercedes, wheel alignments had to be done via the 'prybar' method or some such, where they use a prybar to pull on the suspension while checking on it to see how much slop it has. 90% of your run of the mill alignment rack operators are clueless about this.

Zero1789

Slight update. I took the car to a shop which checked alignment on their Hunter. They said although the camber was out slightly, but it would not cause these issues. Nevertheless, they corrected what they could and the issue is still there. I do beleive him when he says its not a alignment issue, since I took this video where the car is jacked up from the front and stationery. You can see as soon as I release the wheel from centre, it turns itself to the right. I'm thinking it must be something to do with the steering system now.

Only problem is when I scan using a very good Autel scanner, I cannot find any codes in the steering module at all. Steering sensor angle also reads correctly. I'm at a loss.

S-Prihadi

01. Show us your latest alignment report. Before and after please.
I am curious to see what magic they can do without correction bolts to correct what they could for camber : They said although the camber was out slightly, but it would not cause these issues. Nevertheless, they corrected what they could

02. Don't rely on scanner for alignment problems related to suspension system. It will tell you nothing unless it is very severe difference or conflict between steering angle sensor and accelerometer values. Example a dumb azz technician did not set your steering to proper 12 o-clock and lock it while doing works on your steering or suspension and then the result is, steering wheel is say 15 degree off to the right physically while steering system direction is good at zero degrees straight and car will go straight. There then steering angle sensor value will not match the accelerator value, DTC can appear after you drive some distance. I learnt of this when doing camber & caster correction bolts. MB caster/camber correction bolts are not eccentric bolt but single sided groove bolt. So its not a simple bolt spinning to tune the camber/caster but how to orient the groove and depending on LEFT or RIGHT side suspension use and if we want additional or reduction of values. Not friendly to use but it wont ever drift or goes out of adjustment. I recall correction value is max 0.33 degrees or 20 minutes only for those bolts.

03. Your CLS W218 seems more complex than W212. I think it is an airmatic suspension... yes ?
If you care to read the CAMBER spec I gave you the link at post #6 , W218 has 3 different values for camber at 3 different Romess value.
No regular alignment shop will ever buy the Romess inclinometer, too expensive and must have the mercedes adapter too.... too much hassle.
I dont have CASTER value data on me at the moment.










Looking at the W218 supposed front Camber values, if your 1st posting of the alignment front RIGHT being -1degree 33 minutes and if that value is accurate, oh boy that is not pretty at all. Maximum allowable difference between LEFT and RIGHT camber is only 24 minutes for all models W212 and W218, this again your car have exceeded by too far .....by 1 degree 3 minutes. Correction bolts can't help you.



So best seek a properly equip workshop with the right tool and the correct data for your car based on your exact suspension system.
Romess value if out of spec too much is also an indication of some potentially bigger problem/s like bent suspension arms and so on and if your car ever got into an accident before,
they may bring out the big gun, the chassis measuring tool to see if your chassis is still straight or out of whack.

BTW have your car ever had an accident of some sort ?

Have fun troubleshooting..................

Zero1789

Wanted to provide an update to this thread after many weeks.

The issue was not alignment related. Appreciate all the info that S-Prihadi has put into his post but alignment would not cause these issues, especially as the wheels are turning themselves when the car is lifted off the ground. Clearly, there was something more fundamental not working. After having a lot of research conducted on steering racks, I think it became clear to me that it was most likely the cause. The car has an electronic steering rack with a couple of sensors, including a torque sensor which effectively amplifies the driver input. I can only assume this sensor had become faulty and was causing a slightly deviation in torque outout causing the EPS to steer to the right slightly. This can be felt when driving the car. Turning right is easy as pie, turning left requires more steering effort. This was more noticeable at low speeds which makes sense as there is less steering effort the EPS does at higher speed. In the end, a new steering rack rectified the issue. The vehicle was aligned afterward, although it does need repeat alignment as steering is a little off centre. But, the steering effort is now equal both left and right and the vehicle no longer wants to pull to one side.

Rickman30

There are no caster readings, this is the angle that determines if the car drives straight or pulls. The rear toe shows the thrust angle favoring the left while the front is even indicating that if the steering wheel is set straight to the front, it will be as if the car turns left but travel straight and if wheel is straightened it will be turning right not pulling.

If car pulls left, it is possible the camber of both from wheels is the cause, but if caster is off enough it can override these camber readings, it would seem to diminish as speed increases as camber would slowly overtake exaggerated caster and road conditions such as rain prone areas where highways are crowned for water drainage, so the left lane would negate caster, but pull harder in the right lane.

But without caster reading it's hard to determine how the car drives. The camber indicates the subframe may have been pushed to the right of the car, the rear shows possibly a failed bushing or bent arm.

All of this is also based on a properly calibrated alignment machine and a perfectly level alignment rack. Calibration should be performed at min. once a year, I like twice that, I checked my alignment rack level every morning with the weight of a car on it every day.

K-Mac

When all said and done the reality is “OEM” there is no front Camber or Caster adjustment and no rear Camber only Toe / directional adjustment !

New car industry's best kept secret - it is all to do with cost cutting and ever increasing speed of new car assembly lines.

Yes, can fit offset (front suspension) bolts - but inaccurate one position providing a minuscule 1/8 inch (0.3 degree).

We saw the need to fix it right the 1st. time. Providing both "Camber" to resolve costly, premature tire replacement by allowing to adjust and spread load more evenly along with "Caster" to correctly resolve steering pull and improve directional control.

Serious adjustment (up to 2 degrees Pos. or Neg). Easily accessible "single wrench" - Precise / Ultimate direct on alignment rack (under load).

Catering for other then showroom height conditions - high cambered roads with noticeable excess passengers side edge wear. Altered height through extra load or lowering. Fitting wide profile tires or just the (ongoing) ability to cater for curb knocks !

End the frustration of going from one dealer to the next and being told nothing we can do about it…. Front and rear Toe is correct !

SEE SPOILER

AUDI to VOLVO - K-MAC Experience Of Resolving OEM Suspension Shortcomings Since 1964