PS/ABC tandem pump oddities?
12-04-2012, 07:28 PM
#1
MBWorld Fanatic!
Thread Starter
PS/ABC tandem pump oddities?
I've had some ABC problems in the past. I had to have the pump replaced in April as the car had displaying white and red ABC warnings and finally one day blew up (fluid leaked out everywhere and car sank down all the way on the front). I ended up going with a rebuilt pump.
Everything was pretty much fine until then. I did notice the front driver wheel would sink a little bit when the car sat....even for a few minutes it seemed. However, I never got any ABC warnings and the car would go up and down on request. It did this from the day I got the car back when the pump was replaced (don't remember it ever happening before pump was replaced).
Finally...I started getting the dreaded ABC warning again about 6 weeks ago. However, when I turned car off and restarted it..warning went away. Matter of fact, warning didn't come on at all the last month so I figured maybe there was air trapped in the system when the warning came on weeks ago.
Fast forward to last night....I notice at the end of my ride home...that there is a loud groaning noise when I turned the steering wheel...seemed to go away when I hit the gas. There was never any groan noise, not even minor, before last night.
I dicked around with it for about 10 minutes last night....and before I know it, the power steering stopped working altogether and I have a ton of Pentosin under car.
However (and I have not driven car since....only started it in park).....the ABC still lifts and lowers fine....no warning lights are on...and the car didn't sag at all overnight.
The fluid level on ABC is fine...however, the pentosin is basically empty on the PS dipstick.
Is it possible for only the PS side of pump to go out (which I know means I'd have to replace it again).
It's just odd that the ABC is working fine and that fluid level isn't affected.
I'm just trying to diagnose if it might be a PS hose burst.....or whether steering rack is out? Or ?
Everything was pretty much fine until then. I did notice the front driver wheel would sink a little bit when the car sat....even for a few minutes it seemed. However, I never got any ABC warnings and the car would go up and down on request. It did this from the day I got the car back when the pump was replaced (don't remember it ever happening before pump was replaced).
Finally...I started getting the dreaded ABC warning again about 6 weeks ago. However, when I turned car off and restarted it..warning went away. Matter of fact, warning didn't come on at all the last month so I figured maybe there was air trapped in the system when the warning came on weeks ago.
Fast forward to last night....I notice at the end of my ride home...that there is a loud groaning noise when I turned the steering wheel...seemed to go away when I hit the gas. There was never any groan noise, not even minor, before last night.
I dicked around with it for about 10 minutes last night....and before I know it, the power steering stopped working altogether and I have a ton of Pentosin under car.
However (and I have not driven car since....only started it in park).....the ABC still lifts and lowers fine....no warning lights are on...and the car didn't sag at all overnight.
The fluid level on ABC is fine...however, the pentosin is basically empty on the PS dipstick.
Is it possible for only the PS side of pump to go out (which I know means I'd have to replace it again).
It's just odd that the ABC is working fine and that fluid level isn't affected.
I'm just trying to diagnose if it might be a PS hose burst.....or whether steering rack is out? Or ?
12-04-2012, 09:00 PM
#2
Super Member
Join Date: Jan 2007
Location: Sleepy Hollow, IL
Posts: 852
Likes: 0
Received 2 Likes
on
2 Posts
65 Chevelle Wagon w/ C5 frame, 08 ML63, 04 S600, 04 E55,(sold) 00 ML55,(sold) 98 C43-55K Swap
The tandem pump is 2 pumps in one housing driven off of the same shaft. If that makes sence. It is possable that just your power steering side would go out. It may just be a o ring or something stupid. If you want, I may be able to look at it for you if you want. I'm in the nw suburbs and have a ton of pentosin, pumps, valve blocks etc. I stock up for my abc car
12-05-2012, 12:47 AM
#3
MBWorld Fanatic!
Thread Starter
Hey, how can I get ahold of you? I'm in the north burbs.....my normal guy is all booked up for appointments so I'm having it towed someplace in Libertyville tomorrow just to diagnose....but maybe I could take one of those pumps or valve blocks off your hand.
I am familiar with the tandem pump....so I do understand what you mean. I'd probably rather it be the pump again (and I'm 95% sure it is) than the steering rack as I have a feeling if it's not the pump....the pump isn't going to be far behind in terms of replacing again since I've had ABC warnings over the last month.
I am familiar with the tandem pump....so I do understand what you mean. I'd probably rather it be the pump again (and I'm 95% sure it is) than the steering rack as I have a feeling if it's not the pump....the pump isn't going to be far behind in terms of replacing again since I've had ABC warnings over the last month.
