Bar room diagnosis of suspension problem wanted...

[stephenmercedes]

I know it's impossible to diagnose over the internet, but would appreciate a few pointers for me so as to prepare for not being ripped off! Its' a 2001 W203, C240, 134,000 miles on her. It feels decidedly 'skittish' on the road. Not a bouncy feeling like a done shock absorber, but almost like a 'fish tail' type action when she goes above 60mph. The car feels as if it wants to change lane almost.

Like I said, I'm not expecting a diagnosis, but a few options of what you may think may be wrong. The car has a valid MOT from 6 months ago, so if it was anything 'terminal', I would have expected it to have been picked up then, maybe not! Any ideas?

 

[Petrol Pete]

Where to begin ? tyres (condition and suitability) and tyre pressure first (and easiest). Then its up on a ramp to check all linkages then off to somewhere that knows how to do PROPER wheel alignment. Good luck

 

[Petrol Pete]

^^^ P.S . I am in an airport bar. In a few hours time I will be in a different airport bar in a different country. Then in a flying bar for 9 hours.

 

[stephenmercedes]

Should have said, all 4 tires have been checked, & all new within the last 3 months Guess it's off to a ramp then?

 

[grober]

Could be almost anything. Some people make the mistake of thinking they only have to check the front suspension + steering but you have to check the rear suspension also.

 

[stephenmercedes]

Could be almost anything. Some people make the mistake of thinking they only have to check the front suspension + steering but you have to check the rear suspension also.

Instinctively, I think it is the rear that is the source of the problem. I have owned a Toyota Celica GT4 for 10 years now, which is fitted with a unique 'superstrut' suspension (read, expensive!), and I became quite skilled at diagnosing which bit failed on a regular basis, costing almost £2000 in total at one stage to replace the whole darn thing. I just am not use to the W203 yet to diagnose the issue by the seat of my pants, just know all is not right!

 

[grober]

At the rear you have those 5 suspension links to check and the rear subframe mounts [ front mounts in particular] I remember dodgy rear subframe mounts on an old 190 I had which gave a very unnerving floating feeling under de-acceleration

 

[OneForTheRoad]

Instinctively, I think it is the rear that is the source of the problem. I have owned a Toyota Celica GT4 for 10 years now, which is fitted with a unique 'superstrut' suspension (read, expensive!), and I became quite skilled at diagnosing which bit failed on a regular basis, costing almost £2000 in total at one stage to replace the whole darn thing. I just am not use to the W203 yet to diagnose the issue by the seat of my pants, just know all is not right!

Argh the figure of 8's those were the days.

 

[stephenmercedes]

I have now also noticed a squeak from the rear, in addition to a 'sometimes but not always' clunk when coming to a stop, or moving off from rest. Does that narrow it down. or merely add to my paranoia of the rear axle falling off LOL

 

[grober]

My 190 also clunked occasionally till the subframe mounts were sorted ---especially on any back to front or front to back weight transfer.

 

[renault12ts]

Rear subframe bushes without doubt.

 

[stephenmercedes]

My 190 also clunked occasionally till the subframe mounts were sorted ---especially on any back to front or front to back weight transfer.

That certainly sounds a very similar symptom to what I'm experiencing. At the time, did your car also suffer from the rear wallowing around like a drunken marshmallow?

 

[grober]

Not really just that slight floating feeling mainly on the overrun but that might depend on the state of the subframe mounts? the subframe mounts are only one possibility of course.

 

[stephenmercedes]

Now solved...

I booked the car in to a MB Indy dealer for next Thursday, but said I would drop in today so they could diagnose the issue to make sure they had the part in stock. On taking the car out for a test drive, the owner immediately diagnosed a broken rear drivers side suspension arm. He wasn't happy at me waiting a week, so said if I could wait, he would get a ramp cleared and do it now. I was gobsmacked, never had service like it! In and out in less than an hour. Also, the price I was charged was amazing. The drive home was a simple joy, handling now transformed, and now driving like it should.

I need to give the garage a name check, as anyone near Belfast with an MB should make it their 1st stop!

Creevy Autos - independent Mercedes Benz Specialist - Belfast,County Down-Northern Ireland N.I.

Old nasty part!



New shiny part being fitted...

 

[renault12ts]

You're lucky..usually more than two weeks before I can get a slot in Creevy. Agreed though...easy to pay. Never paid for a STAR session yet.

 

[grober]

looks like what is known as the thrust arm 370
or push rod 3 in this diagram

 

[grober]

This is a further illustration on the earlier W124 but the design is basically the same on the W203
Mercedes W124 Rear Suspension Guide - PeachParts Mercedes ShopForum