CLS320 CDI judders when accelerating (2500-3000rmp)

[Punz]

Hi all,
My 2005 CLS 320 CDI 7G Auto on 100k has a fault when accelerating. It seems to happen when the car is warm between 40-60mph in 3rd and 4th gear at about 2500rpm-3000rpm.

When at about 40mph in 3rd gear and you put your foot down, the revs go to 3000 and the car begins to judder and shake. After juddering for a few seconds and not really increasing speed it switches to 4th gear in which it accelerates without any juddering until at about 2500rpm. When it gets to 2500rpm it starts to judder and vibrate again up to 3000rpm. It then stops when it goes into 5th gear and accelerates smoothly as it should upwards without any vibration.

It doesn’t always do this and it happens about 50% of the time when at 40 and you put your foot down. When the car is juddering, if you immediately let go of the accelerator pedal and then put your foot flat again, sometimes it accelerators all the way through without any juddering and other times it starts to judder again.
Initially from reading online and calling Mercedes Specialists they advised it may be the transmission. A Mercedes independent specialist changed all the ATF fluid and filter last week but it doesn’t seem to have fixed the fault. (It appears this was the first time the fluid had been changed because it was filthy and had not been changed according to the service history.)

Normally it never goes into limp mode and there are no warning lights displayed when it judders. But the last time it happened the car went into limp mode. I’ve ordered a fault code reader so hopefully there will be a fault code registered from the car going into limp mode. The car had its filters changed at about 87k but I have ordered another fuel filter just in-case.

I’m probably going to have to go to another specialist to get it looked at but would appreciate some advice as to what it could possibly be from this forum beforehand.

Any theories anyone?

 

[Punz]

This video is what happens when I try to accelerate.

IMG 7583 - YouTube

· 10 seconds - At 40mph I put my foot down and start to accelerate

· 11-13 seconds – you can see the car shaking and although the revs are high the car is not really accelerating in speed

· 14 seconds- you see the revs dip down and the car shifts to the next gear

· 15-17 seconds – the car increases speed from 45-55mph smoothly without any vibrating

· 17-19 seconds – the car starts frantically vibrating again

· 19-21 seconds – although I still have my foot steady on the accelerator the whole time the revs dip down and the car now goes into limp mode not letting me increase speed.

 

[Zu11y]

Hi mate, im no expert at this but my car is having similar issues, and was advised that it may be the turbo actuator or the inlet shut off motor, during the diagnostics the latter was shown but after a few days my car was stuck in limp with the engine light on.

 

[Dieselman]

I would think it is the torque converter lock-up clutch friction material.

Before going too far have a glycol test performed and then let an auto gearbox specialist have a look.

 

[Punz]

The engine light doesn't come on but the car feels like its in limp mode and has alot less power.

The car does have a Valeo radiator but according to this guide I thought it only happens to 2000 - 2003 cars?
http://www.mbclub.co.uk/forums/engine/41764-official-test-proceedure-valeo-radiator-issue.html
Mercedes-Benz Owners' Forums - View Single Post - Identification of the early Valeo Radiator?

Driving the car today for the first time the juddering occurred when in 2nd gear at about 20mph when I put my foot down.

 

[SL300-24]

I think that it may be a turbo/inlet port motor problem. I would recommend that you get the fault codes read before doing anything else.

 

[Punz]

Ive had the car scanned with a OBD code reader and it didn't bring up any fault codes apart from a oxygen sensor (P0132) and glow plug control (P0670)? Very strange considering it goes into some sort of limp mode if I hold down the accelerator all the way through the juddering.

I also wanted to test if the car does this when its cold; so it was at about 45 degrees and in 2nd gear at about 30mph when I put my foot down and car juddered so the problem now seems to be occurring in other gears too.

Going to get it connected upto STAR tomorrow for a proper diagnostics

 

[Punz]

After looking through lots of Mercedes specialist and trying to decide which one to go with I decided to take the car to Wayne Gates Mercedes in Harrow after reading several good reviews online.

Just a little background about the car, I purchased it in the last week of December from what I thought was an excellent private seller. The seller didn't let us test drive the car at the time because he wanted to see fully comp insurance paperwork. We had 3rd party insurance and obviously the cash to pay for the car. He took us for a short drive and the deal was done. On the way home, turning out of his road we initially felt the judder but obviously having not experienced this before we thought it was the traction kicking in (it was wet and lots of loose stones). After experiencing it a couple more times I got home and contacted him to tell him there was a serious problem and offered to bring the car back. He refused and said the deal was done and car was sold as seen. I'm still trying to negotiate with the seller but he is completely denying there was any fault with the car when it was sold.

I had previously got the AFT fluid changed so Terry from Wayne Gates said he would take the car in for a week to try and diagnose it. We initially thought it was the gearbox or torque convertor but 3 days after I received a call from Terry explaining it was probably about the worst juddering fault he had ever felt and had found iron fillings coming out the turbo. He knew it wasn't the torque convertor because if it was faulty the car would vibrate moderately. If it was the gearbox it's likely to vibrate when actually changing gear rather than in the gear. He tested this by keeping the car in manual mode and the juddering still took place at about 2500revs- 3000revs. He explained the juddering is being caused by the exhaust manifold which is double skinned breaking down and being sucked into the turbo. So I ordered a recon turbo and Terry ordered in the manifolds and gaskets.

I'm happy to say the problem has finally been fixed. It was a very expensive fix but it is common for the exhaust manifold to fail on these engines at about 100k. Terry at Wayne Gates was absolutely excellent. He kept me updated at all times throughout the repair and even offered to try to explain the problem to the previous seller to help with my negotiating. It certainly pays off to take the car to a specialist otherwise you will just end up getting messed around and replacing lots of parts unnecessarily.

 

[cbards]

Hi all,
My 2005 CLS 320 CDI 7G Auto on 100k has a fault when accelerating. It seems to happen when the car is warm between 40-60mph in 3rd and 4th gear at about 2500rpm-3000rpm.

When at about 40mph in 3rd gear and you put your foot down, the revs go to 3000 and the car begins to judder and shake. After juddering for a few seconds and not really increasing speed it switches to 4th gear in which it accelerates without any juddering until at about 2500rpm. When it gets to 2500rpm it starts to judder and vibrate again up to 3000rpm. It then stops when it goes into 5th gear and accelerates smoothly as it should upwards without any vibration.

It doesn’t always do this and it happens about 50% of the time when at 40 and you put your foot down. When the car is juddering, if you immediately let go of the accelerator pedal and then put your foot flat again, sometimes it accelerators all the way through without any juddering and other times it starts to judder again.
Initially from reading online and calling Mercedes Specialists they advised it may be the transmission. A Mercedes independent specialist changed all the ATF fluid and filter last week but it doesn’t seem to have fixed the fault. (It appears this was the first time the fluid had been changed because it was filthy and had not been changed according to the service history.)

Normally it never goes into limp mode and there are no warning lights displayed when it judders. But the last time it happened the car went into limp mode. I’ve ordered a fault code reader so hopefully there will be a fault code registered from the car going into limp mode. The car had its filters changed at about 87k but I have ordered another fuel filter just in-case.

I’m probably going to have to go to another specialist to get it looked at but would appreciate some advice as to what it could possibly be from this forum beforehand.

Any theories anyone?

I had exactly the same, I have a CLS 320 cdi 2007 with 120,000 miles on the clock, mine was just starting to do this intermittently. My brother is a mechanic of some years experience and said that the turbo actuator which is common fault on the V6 3l cdi engine was likely to be at fault. I had planned on just replacing the turbo even though it was not smoking or anything, just to cure it. But a few days ago I spotted an advert from a local garage for a carbon engine clean for £70, I think it was called Oxyhtech. I’m writing this 3 days after having it done and the results are astonishing. No juddering, as yet , as soon as the accelerator is down it instantly picks up. I’m guessing that I have 10/15% more power. I’ve just absolutely ragged it and I was getting better fuel economy than if I was driving carefully before it was done. Maybe it’s too early to say if this has worked but I think it has.