Marek.1290

So having some issues with the GL 450 that we have. The problem is, whenever It accelerates it loses traction on the front left wheel, or maybe that the only one that's being powered, also happens when turning left. Also when braking ABS kicks in "too quickly" at least it feels like that, if its wet outside it basically almost every time. A couple of months ago the front shocks were replaced but this started around 2 months ago. Now the rear shows were replaced because they felt bad and the car was sagging on one side, I know this may be the right rear bag that can maybe cause this because when I was replacing trhe shocks I noticed that on the right side the bag was able to be pushed in but on the left, it was hard as a rock. Also for some time now it shows an airmatic malfunction when trying to lift it, and the car has to be restarted in order to lower it back down. Has anyone experienced anything similar? What might this be? Do the rear bags need to be replace also?

wannawagon

could you maybe tidy up the wording - what are "shows" replaced?? a little hard to get what is happening - also a couple is around 2 months but don't think it is shocks (was it same time) - unless you had a leaking bag as well?? or did you change the front shocks and bags?? (I know they are one unit but can be seperated - I do)

how heavy is the acceleration to make it lose traction? just gently or are you planting foot hard

shocks won't cause it to sag - just unstable ride

any codes? could be a wheel sensor is unplugged - but would normally give abs/asc error on dash

91stealthes

I think you have 2 separate issues.

First, "losing traction" and ABS feeling could be a couple things...wheel speed sensor, bad pads/rotors, bad tires, uneven tires.

Second, airmatic malfunction could be bad compressor, leaking block, leaking bag, disconnected line.

You also could have replaced the shocks with the incorrect shocks. Do you have ADS? If so, did you replace with ADS shocks?

Do all 4 tires match and were they installed at the same time?

Marek.1290

I checked before replacing and I do not have ADS and I replaced the bags and shocks, the whole strut, in the front and in the back so far I only replaced the shocks. Also when I did the shocks in the back on the one side the bad "compressed" down when the car was jacked up but on the other side it was stretched out towards the top and was hard as a rock, this also made it really difficult to align the suspension arm so that I could put the shocks' bolt through. I did remove the fuses for the bags/compressor as others have instructed to do so. All 4 tires are not the same but match on each axis. I will try and check wheel speed sensors tomorrow.

Marek.1290

I checked before replacing and I do not have ADS and I replaced the bags and shocks, the whole strut, in the front and in the back so far I only replaced the shocks. Also when I did the shocks in the back on the one side the bad "compressed" down when the car was jacked up but on the other side it was stretched out towards the top and was hard as a rock, this also made it really difficult to align the suspension arm so that I could put the shocks' bolt through. I did remove the fuses for the bags/compressor as others have instructed to do so. All 4 tires are not the same but match on each axis. I will try and check wheel speed sensors tomorrow.

Max Blast

So both of your rear airbags are suspect, at least one is fully blown, and both should be replaced immediately. Fortunately for you this is a very easy DIY. Also run a code reader for any wheel speed sensor Malfunction codes that are probably causing your ABS and ESP issues.

91stealthes

Which ADS shocks did you put in?

You mention all 4 tires match on each axis. Are you referring to the original size of the tire or the current measurements. I've heard rumors that mismatched tires can cause a bunch of issues...as well as not being a good idea with true AWD vehicles. I would think wheel speed sensor fault is more likely, but don't dismiss the tires.

Marek.1290

All measurements are exactly like the original and I have goodyears, the same ones, on the front and another matching brand and tread on the rear. The remaining tread is also roughly the same. I will order new bags to see it that might help with some of the slippages and will also check wheel speed sensors.

Marek.1290

I don't remember the exact code but I think there might have been one for some esp issue,I will check again tomorrow and will also order the bags. I wasn't too sure if it was the bag itself or other things along the way like mentioned. As of right now the right side sits about 2-3 inches lower than the right. DIY seems easy enough so I'll get those replaced as soon as I can.

91stealthes

Great. If all 4 tires actually have the same tread depth and diameter, I would think it's not the tires.

I also don't think the bags have anything to do with your slippage, but as you say, at least one is blown and one side is constantly sagging. I'd replace both bags ASAP, as your pump is taking a toll continually running. I personally put Bilstein bags on mine. RockAuto had the best price.

I still believe your issue is the wheel speed sensor. Get the codes read to tell you which wheel is causing the issue. Being you say you feel slippage on the driver front, I would assume it's that sensor, but who knows without reading the codes.

expl0rer

Just adding my 2 cents here. As I understand, you have two Goodyear tires with the same tread pattern on the front axle and two tires of a different brand, which are from the same brand, with matching thread patterns as well. The front tires are evenly worn and the rear tires are evenly worn.

Keep in mind that the diameter of a tire (new) in the OE size could be different for Goodyear, Continental, Pirelli, even for different types from the same manufacturer. To give you an example, I have a 2010 550, OE tire size is 295/40R21. I just replaced the tires which were on the vehicle when I bought it. Those were Pirelli PZero in the OE size. New, the PZeros have overall diameter 30.5 inches (77.47 cm). I replaced all four with Continental DWS06 in the OE size, whose overall diameter is 30.3 inches (76.96 cm).

Let's say that I got two new PZeros and two new DWS06s. The diameter of the PZeros and DWS06s are within 1% when new, so that is fine. (Staggered setups aim for > 1% diameter difference between front and rear tires, and should always use the same tire.) But the PZeros will wear much quicker so eventually, the diameter difference will increase above 1%. If your front tires are worn out more than the rear tires (or vice versa), even though you have similar tread depth on all tires, your car could react to the overall diameter difference.

The chance of wheel speed sensor(s) being at fault is higher, but the tires are not to be ignored, especially if you have two types of tires on your GL.

Max Blast

Good one.

Marek.1290

Well so far I replaced the wheel speed sensors and it seemed to get better as in barely there. Today I also replaced both rear bags but the right side, the one that was sagging, is not inflating at all. Tried to raise the car, nothing, it just sits as low as it will go. I will try and check the line as far as I can go tomorrow but what else might I check it terms of the bag and air situation. The air block that is in the front? Maybe a ride height sensor?

wannawagon

Marek.1290

I didn’t take it off or disconnect it, I was able to pull the back out from the wheel side not from underneath. So really what can it be, bad sensor? The block for the line in the front? Or the line?

Marek.1290

So just to give an update if anyone else ever reads this. I ended up taking it to a shop after the bag replacement didn't help, they said it was the valve block but when they went to install it they also said my air pump is cracked. At this point, I think I will try and replace the valve block since its easily accessible and see where that gets me. The car held its height normal before this and even after only the one wheel was off so I feel like the valve block might be able to help with that, but the air compressor being cracked I will have to wait and see if it will work enough to keep it level, maybe it just wont be able to raise it to the raised level. As for the traction issues I will have to wait for when the car is level and also might need to get new wheel speed sensors because the ones I got are non-genuine and I have abs/eps error on the dash.

wannawagon

Did you get any codes. Really important (and economical) to get the codes. Lots of things will cause abs/traction error

would not expect the compressor to just effect one corner

i use an Autel scanner that only came with Mercedes software. Can buy other manufacturers for about $10 us each. The scanner was only about $150 Australian

Marek.1290

Well the only scanner I have for this car is a cheaper phone app one. I found this one I found is also Autel, its the Autel MaxiDiag MD806 Pro, do you know if its similar to the one you have? I just don't want to pay the price of the scanner ($250) and have it not be able to show me everything I need.

As for the compressor, I thing I'll replace the valve block and see what it does.

Max Blast

Unless you’ve had the overheating compressor warning, don’t expect to find any codes - even on a genuine mb star / das system.

my compressor was cracked as well. No warnings, cautions or codes. Just a godawful racket.

Marek.1290

So i took the car back after they said it was the compressor along with the valve block. I took it to another mechanic to check why I had the abs/esp light come on. He turned it on and off and tried raising each corner and since I left I had the abs light stay on. Could it be that he disabled the wheel speed sensors? I replaced the air block myself and now it raises and lowers perfectly fine without the need of a new compressor. So now the only issue is the abs/esp light. Could It have gotten disabled with a better scan tool? Or could it be from them no being genuine Mercedes part?

Max Blast

Yes it is possible to get stuck in a mode where ESP and ABS are disabled and/or malfunctioning by interrogating the ABS system. Although from the sound of your initial symptoms I don’t think that’s what happened, It sounds like you had a couple of wheel speed sensors going out anyway. And when that happens, usually after charging a dying battery, you get the symptoms you have. Glad to aromatic issue sorted out hopefully your new valve block will last a long time. If the one you took out was the original hang onto it!

eric_in_sd

"Aromatic" lol

Yeah it's tempting to say the system stinks when it no worky.

OP, you were asking about scan tools. As far as I can tell, the hierarchy goes: Bluetooth dongle + Torque => MBII => Autel MP808 => DAS
I am in the process of buying (trying) Benz Ninja's DAS setup. It is modestly more expensive than the MP808. The genuine article is, of course, absurd for us survivalist tinkerers.
There are a bunch of Autel units. There is no reason to get anything cheaper than the MP808, which offers "bidirectional" - that is, it can send commands to the ECU, etc. - interface.
If you get a cheaper Autel, you may as well go much cheaper and get the MBII, which gives you an impressive ability to query the system. It will give you oxy sensor voltages and so forth.
Torque is great for displaying and clearing codes. Just don't leave your bluetooth dongle in place full time. Scotty Kilmer alleges some can fry your engine computer.

There are similar computers to the Autel MP808 from other makers. I could not tell you which of those is more or less legit.

Why not go directly to the off-label DAS setups? It's a minefield. I am hoping Benz Ninja has in fact done his homework and sells a reliable and virus free unit. See, we did have something of a problem with viruses coming out of China ...

Also, the Autel gives you ability to work with a whole range of vehicles. My son just bought a Dodge pickup; the Autel was already useful for querying the ECU to see if there were any dormant trouble codes.

Max Blast

The other thing about Ben’s ninja set up is that to get full use of it you have to allow him/her/it to remote into the computer they send you. Some people may find that a immense benefit, some others may find that a huge security risk.

A clone of the real deal should be had for around $900.

eric_in_sd

Hm. Not permanently, I hope. That's just for setup, right?

The price is about the same between his stuff and others; the benefit is a pre-screened installation. I just don't have the bandwidth to debug. Installing a virtual machine and WIS was bad enough.

EWT

The virtual machine WISs have a pretty steep learning curve. I've finally gotten somewhat good at using it after about 3 years of ownership although I still find the search feature to be amazingly worthless. I was searching using the title of a printed WIS document I had a copy of and it didn't find anything. I then discovered the index of documents by number rather than by section of the vehicle and found what I needed. Not a bad value for $20-30 though.

The other thing I figured that really improved the usefulness of it was how to print things on paper so I don't have to haul a laptop to the garage/under the hood/under the car. You print to .pdf, save to the virtual machine desktop, then you can drag the document from the VM desktop to File Explorer.