abc pressure too high & running at 250 bar
Thread Starter
Super Member
Joined: Jul 2010
Posts: 955
Likes: 127
From: Kansas
2003 E55, 2003 SL55, 2014 CLS63, 2018 q50 Redsport, 1968 Camaro SS, 1999 Trans am Firehawk
abc pressure too high & running at 250 bar
Tried on the SL forum, but didn't get any help and I know you guys also have ABC on your cars.
I just recently did the following to my SL55:
replaced front valve block
replaced front valve block accumulator
rebuilt rear valve block
replaced rear valve block accumulator
replaced pulsation dampener
replaced return line accumulator/dampener
replaced hose that goes from front valve block to left strut
replaced hose that goes from front valve block to right strut
replaced hose that goes from pump to pulsation dampener/pressure limiting valve
here's my problem, when I start the car pressure builds to 250 bar. Pressure is supposed to be regulated to 200 bar. The high pressure in the system is causing fluid to just pour our of the pressure limiting valve. I replaced the pressure limiting valve thinking it might be the problem, but the system still remained at 250 bar and after about 10 minutes at idle the new pressure relief valve starting pouring out fluid.
The hose that goes from the pump to the pulsation dampener originally had some sort of metal inside of the first flexible rubber hose section, very similar to a power steering line that has it dampen noise as a flow restrictor. When I replaced that hose I had one built with flare nut ends and as a result it does not have the piece of metal inside of the first rubber hose.
I'm thinking either the new hose is the reason the pressure is too high and I keep blowing pressure relief valves (not sure if they are trashed now or not) or maybe the suction restrictor on the pump isn't working correctly (at some point in the past someone had replaced the pump and for some reason the wiring going to the suction restrictor on the pump was cut and then spliced back together). Anyone have any clue on this?
The pressure relief valve is leaking out of the bolt next to the pressure sensor. Originally it had what looks like a cap in it in the middle. When it started leaking this cap blew off and there is an allen wrench head underneath now showing. Do I need the cap thing back on to get the thing to stop leaking? (I have no clue where it is btw) Do I need to turn the allen wrench head at all and if so which direction and how much?
I am totally lost here and super frustrated as I have spent an enormous amount of time and money on this suspension refresh project.
I just recently did the following to my SL55:
replaced front valve block
replaced front valve block accumulator
rebuilt rear valve block
replaced rear valve block accumulator
replaced pulsation dampener
replaced return line accumulator/dampener
replaced hose that goes from front valve block to left strut
replaced hose that goes from front valve block to right strut
replaced hose that goes from pump to pulsation dampener/pressure limiting valve
here's my problem, when I start the car pressure builds to 250 bar. Pressure is supposed to be regulated to 200 bar. The high pressure in the system is causing fluid to just pour our of the pressure limiting valve. I replaced the pressure limiting valve thinking it might be the problem, but the system still remained at 250 bar and after about 10 minutes at idle the new pressure relief valve starting pouring out fluid.
The hose that goes from the pump to the pulsation dampener originally had some sort of metal inside of the first flexible rubber hose section, very similar to a power steering line that has it dampen noise as a flow restrictor. When I replaced that hose I had one built with flare nut ends and as a result it does not have the piece of metal inside of the first rubber hose.
I'm thinking either the new hose is the reason the pressure is too high and I keep blowing pressure relief valves (not sure if they are trashed now or not) or maybe the suction restrictor on the pump isn't working correctly (at some point in the past someone had replaced the pump and for some reason the wiring going to the suction restrictor on the pump was cut and then spliced back together). Anyone have any clue on this?
The pressure relief valve is leaking out of the bolt next to the pressure sensor. Originally it had what looks like a cap in it in the middle. When it started leaking this cap blew off and there is an allen wrench head underneath now showing. Do I need the cap thing back on to get the thing to stop leaking? (I have no clue where it is btw) Do I need to turn the allen wrench head at all and if so which direction and how much?
I am totally lost here and super frustrated as I have spent an enormous amount of time and money on this suspension refresh project.
Super Member
Joined: Mar 2010
Posts: 643
Likes: 72
From: London UK
2013 W204 C63 AMG, 2008 W221 S65 AMG
Tried on the SL forum, but didn't get any help and I know you guys also have ABC on your cars.
I just recently did the following to my SL55:
replaced front valve block
replaced front valve block accumulator
rebuilt rear valve block
replaced rear valve block accumulator
replaced pulsation dampener
replaced return line accumulator/dampener
replaced hose that goes from front valve block to left strut
replaced hose that goes from front valve block to right strut
replaced hose that goes from pump to pulsation dampener/pressure limiting valve
here's my problem, when I start the car pressure builds to 250 bar. Pressure is supposed to be regulated to 200 bar. The high pressure in the system is causing fluid to just pour our of the pressure limiting valve. I replaced the pressure limiting valve thinking it might be the problem, but the system still remained at 250 bar and after about 10 minutes at idle the new pressure relief valve starting pouring out fluid.
The hose that goes from the pump to the pulsation dampener originally had some sort of metal inside of the first flexible rubber hose section, very similar to a power steering line that has it dampen noise as a flow restrictor. When I replaced that hose I had one built with flare nut ends and as a result it does not have the piece of metal inside of the first rubber hose.
I'm thinking either the new hose is the reason the pressure is too high and I keep blowing pressure relief valves (not sure if they are trashed now or not) or maybe the suction restrictor on the pump isn't working correctly (at some point in the past someone had replaced the pump and for some reason the wiring going to the suction restrictor on the pump was cut and then spliced back together). Anyone have any clue on this?
The pressure relief valve is leaking out of the bolt next to the pressure sensor. Originally it had what looks like a cap in it in the middle. When it started leaking this cap blew off and there is an allen wrench head underneath now showing. Do I need the cap thing back on to get the thing to stop leaking? (I have no clue where it is btw) Do I need to turn the allen wrench head at all and if so which direction and how much?
I am totally lost here and super frustrated as I have spent an enormous amount of time and money on this suspension refresh project.
I just recently did the following to my SL55:
replaced front valve block
replaced front valve block accumulator
rebuilt rear valve block
replaced rear valve block accumulator
replaced pulsation dampener
replaced return line accumulator/dampener
replaced hose that goes from front valve block to left strut
replaced hose that goes from front valve block to right strut
replaced hose that goes from pump to pulsation dampener/pressure limiting valve
here's my problem, when I start the car pressure builds to 250 bar. Pressure is supposed to be regulated to 200 bar. The high pressure in the system is causing fluid to just pour our of the pressure limiting valve. I replaced the pressure limiting valve thinking it might be the problem, but the system still remained at 250 bar and after about 10 minutes at idle the new pressure relief valve starting pouring out fluid.
The hose that goes from the pump to the pulsation dampener originally had some sort of metal inside of the first flexible rubber hose section, very similar to a power steering line that has it dampen noise as a flow restrictor. When I replaced that hose I had one built with flare nut ends and as a result it does not have the piece of metal inside of the first rubber hose.
I'm thinking either the new hose is the reason the pressure is too high and I keep blowing pressure relief valves (not sure if they are trashed now or not) or maybe the suction restrictor on the pump isn't working correctly (at some point in the past someone had replaced the pump and for some reason the wiring going to the suction restrictor on the pump was cut and then spliced back together). Anyone have any clue on this?
The pressure relief valve is leaking out of the bolt next to the pressure sensor. Originally it had what looks like a cap in it in the middle. When it started leaking this cap blew off and there is an allen wrench head underneath now showing. Do I need the cap thing back on to get the thing to stop leaking? (I have no clue where it is btw) Do I need to turn the allen wrench head at all and if so which direction and how much?
I am totally lost here and super frustrated as I have spent an enormous amount of time and money on this suspension refresh project.
You may find that the ECU has a fault in the output stage for the control of this restrictor valve.
Thread Starter
Super Member
Joined: Jul 2010
Posts: 955
Likes: 127
From: Kansas
2003 E55, 2003 SL55, 2014 CLS63, 2018 q50 Redsport, 1968 Camaro SS, 1999 Trans am Firehawk
tried testing the suction restrictor valve and the return line hose from the rear valve block exploded due to too much pressure FML. I've decided to just take it to an indy shop and have them deal with it and it'll cost what it costs.
