05CL55

Man, this car is beating me up right now, stiff as heck. Not bouncy, but rock solid and squirming all over the place on every little bump.

I've had the same setup for years, and the velvet ride is LONG gone.

My ABC needs repairs though, hoping someone can tell me which one would be the culprit, if any. No ABC errors, and raise/lower works fine, fluids are topped. Only symptom is the HARD ride, and a hissing noise from the passenger side pulsation/damper and/or valve thats attached to it.

- Front valve block needs changing, front end drops after couple days. Can live with that for now since thats a $1400 part.
- Pulsation Damper needs change, hums, drones, vibrates. Just ordered today.
- Hissing noise from pulsation damper and valve/sensor area (don't know exactly which) for about 30 seconds after car is turned off.
- front pressure reservoir bulb was just changed, some knucklehead told me that was the pulsation damper so I replaced it, goodbye $200 bucks!

I have the budget to fix all this, I'm just scared to make another mistake for 1, and secondly, if I can spread these repairs out over the next couple weeks to save costs after the holidays.

If I should replace it all now, with a helpful explanation so I can understand it, then thats what I'll do come monday.

ch33sehead

I think it's better to replace it all at once rather than one by one. Trash/dirt/debris from dirty system can ruin a new part. Also there's no point in doing the necessary services over and over again when you can do it once. I don't know if it's necessary but I think rodeo should be done after each part is replaced to bleed all new air introduced to system (the fast way). No sense doing 5 rodeos.

It's also unusual for weak ABC system to ride harder. Usually it rides softer. Maybe your pressure relief valve is not diverting pressure back to return properly? ABC pump only supposed to supply 200bar (~3000psi) of pressure. Relief valve might be stuck open, causing system overpressure? I would recommend getting someone with STAR to monitor the PSI. Once that pulsation damper blows, it's likely to kill the pressure relief valve/sensor. That's probably what's causing the hissing and harsh ride. It's usually a better idea to order the valve/sensor because it comes w/ the attached pulsation damper. No point in buying 2 of them, but that is the gamble.

05CL55

I think your right ch33sehead. I just called and ordered the valve (pressure valve) as well.. An extra $800 bucks though, but something tells me thats part of the problem. I also heard it could be the sensor in the valve, good thing is the new valves all come with new sensors, they don't sell the sensors separate anymore.

As far as the valve block for the front end. WOW, just found out that thing is $1500!! Tech says that this valve shouldn't contaminate system, but will continue to drop the front end after several hours. Says if I'm ok with that for now, I can get buy, and replace that valve later.

I also ordered a new filter and I'm gonna flush first, if all goes well, leave it be, if its still not back to the way it used to ride, then I'm gonna have the rodeo done.

ch33sehead

We usually don't do flushes anymore. The new "Mercedes approved" method is to put a new filter in, do 2 rodeos, and then put another new filter in. So you just buy 2 filters.

alex-300te

mmm hard ride can be related to abc ecu software,easy to do with mb start and flash the ecu, did that on both of my cl's, i sold my cl 600 today 78k milles never a problem still driving a 500 with 56k milles and only a block was changed and was my fault for not doing filter routine like i ussed to do. btw front block valve new stile with dust cover is under 1200 buks dont trust every body out there do some research i can give you my indy phone number in tx, he loves the cl's and would talk to you for hours on the phone he's the man

05CL55

I just changed the pulsation damper, front valve block, and filter with fluid, got a white abc eror, car wont raise, rear is at its last height left, font is on the gound.

Errrggghh

Also, i tried adding 1 bar (15psi) to the tank to help kick start the pump....nothing...

ch33sehead

Are you doing the install yourself? Do you have STAR / SDS ?

05CL55

Myself. I changed the damper yesterday, no problems, No errors, drove car. Today i did the valve block, filter, topped off fluid, but car wont raise back up

05CL55

Definitely convinced it has something to do with getting the pump primed or kick started. If i add 15psi to the tank, i can hear the pump struggling for the first 10 seconds then it shuts off. With no psi, the pump doesnt sound like its even trying to kick on.

Should i increase psi? Should i bleed somewhere, maybe theres a bunch of air in there?

radride

Of you're seeing 15psi/1 bar then your pump is toast. I believe it runs at 2000-3000psi.

R.K.

ch33sehead

He's talking about adding PSI to the reservoir to prime the pump to bleed the pump. Every time you remove parts from ABC system you introduce air. This air needs to be bled out of the system.

You need to lift it off all 4 wheels, open each bleed screws (slowly!) til you see fluid and then close them. Do this for each of the 4 bleed screws. Put the car back down, then start the car, press up/up/down/up/up/down about 5-6 times. Keep checking fluid levels while doing this. If doing this a couple times this doesn't get all the air out then you need to do rodeo a couple times.

05CL55

Thanks ch33se, I'm gonna bleed the 4 and give it a shot. If you can think of anything else, let me know to help me save some $$. Cause after bleeding, im going have to take it in, which means a tow truck $$ and probably much more money for the stealership.

So far I'm stuck at that point though. Rear is fine, front dropped all the way.
With 15psi in the reservoir tank, on first start the pump will try and run for about 5-10 seconds before shutting itself off. Raise/lower button does nothing and still got a white ABC error.

I'm really hoping I can prime this pump as I'll feel really stupid when the tow bill ends up costing what the labor would have been to had the stealership done it in the first place. My hands will probably smell like hydraulic fluid for the next week.

Btw, are you bleeding with the engine off?

05CL55

DAMN.... get this...

I just checked the electrical connections. 1 the female was bad (misaligned) and the second connector the male was bent and wasn't making contact. I was going nuclear crazy last night trying to solve this, sprayed hydraulic fluid all over my garage trying to pressurize the pump, spilled hydraulic fluid after the return line popped off the reservoir from pumping air into it, and was about to tow this in tomorrow, all cause the darn connectors weren't at best.

Sheeese!!!

Started car, didn't need to pressurize or anything, just popped right up! errors gone!

radride

^^Wow. You got luck there. Glad it all worked out.

R.K.

05CL55

yeah I did. Only problem is the car still rides hard, but the dropping after being parked has stopped. Car also still hisses for 20 seconds after shut down.

The hard ride to me is actually the worst. I wonder if theres a dampening sensor or something somewhere they may be bad. The rear primarily is hard, both sides.

biker349

read somewhere that accumulators can cause the hissing and possibly hard ride.

05CL55

yes, post #6 the damper/accumulator (attached to pressure valve) are the same thing, that was replaced, as well as the front reservoir attached to the valve block.

Only thing left I can think of, is the pressure valve. Thats where the hissing sounds like its coming from.

OCKlasse

Which damper was replaced? The one off the front valve block or the one off the pressure relief valve?

05CL55

Both. First the one with the balve block, then I changed the one with the pressure valve too

OCKlasse

No difference in ride? Still the hiss? I have the exact same hissing sound. Looking forward to your results.

05CL55

Yeah, that hissing still won't go away, and it still rides hard. I even raised the car back with the stock ride height links, still pretty hard. If I'm in a turn and I hit a bump, the car will get skippish across the bumps.

Hey where did you find a grille like that for a histrionic car? I've been looking for 1 of those.

OCKlasse

Mine is for Distronic. I believe eBay should have them.

05CL55

Do you remeber the seller? I've been trying to find one that works with my distronic too.