Marcus Frost

Background:

Late build 2003 E55 AMG.
35k Miles.
For all intents and purposes, stock.
Gently driven, always warmed up and cooled down properly. No road course time, a few drag strip passes.

Last time I was at the drag strip I made a few passes on my winter tires (was waiting for backordered PS2s) and noticed my trap speeds were pretty low. It was VERY hot that day, in the upper 90s easily track side, if not hotter, and my best trap was 111mph with the heat blasting down the track to help with cooling. Of course, I had to take off real easy cause the snows wouldn't hook up to save their life, so this was my first "hrm" event. It was very hot, so it is concievable that some of that was due to heat, but the trap speed was a bit low.

It has been very hot here in Chicago over the summer. Very hot, and very humid. Not good for performance. The car, of course, has felt sluggish because of this insane heat. The car had lost bit of oomph but nothing I was ready to say "something is wrong" because it was so hot outside. Remember, I know this car has trouble dealing with heat so hot humid air is definitely not a good thing for this car to help keep performance up.

For the first time in God knows how long, we had some low 70 degree days this week and I was finally able to get the car out in some decent air temps to see if she would pep up a bit. She didn't. In fact, last night I had taken her on a little 40 mile trip to take care of an errand and getting back on the highway, there was definitely something wrong. It didn't fall flat on it's face, but it felt only about as fast as my old E55. I backed off and did a few 2nd a 3rd gear punches and she was not running well. Something was wrong.

I brought in the car this morning - this is where I really need to put in a plug for Loeber Motors and my service adviser there Tom Lood - I've never been so pleased with service from any dealership, be it BMW, Audi, MB, whatever. On my way there, the car has pepped up. It's running better. It's not 100%, but better. I get to my dealership and I told my service adviser he needs to flow test my water pump because I think it is beginning to fail. He said he'd take it for a drive and see if there are any codes. It's hard for a service guy to write up the labor to remove and flowtest a pump based on a customer's request, so I was hoping something would happen so they could pull the pump. Sure enough, they found codes for it in the DME. My pump is failing. The car won't get the new pump until next week because according to my service guy there are very few of them in the country right now. I don't know how many, but very few. I'm getting one of them next week.

Thoughts:

This is troublesome problem. The biggest issue is that it's real hard to diagnose. I have to give credit to the posts on here because from a technical standpoint it's really hard to know why a car is down on power without going through a lot of diagnostic procedures, so the stuff I read on here, especially from Vadim, really helped me know right away what needed to best tested first - sure enough, it was the culprit. I didn't even bother hooking my OBDII scanner because I didn't need to - if these guys wouldn't have found any codes when I took it in, that's when I would have done that.

What advice can I give? That's a difficult question. Not everyone should go out and get all paranoid about this and start asking for coolant/water pump flow tests. Be smart, and if you think something is wrong, go out and test. Give it sometime. The fact that this is not a total upfront failure, but appears to be something that will take time, your best bet is to run it through it's paces and when you REALLY finally feel something is wrong, take it in, tell them about the problem, have them pull the codes, and if they are willing to, have them flow test the pump.

I had a couple of data points to refer to, old and new trap speeds, a good amount of seat time, etc - but not everyone may have this. The other factor is that there is definitely a certain amount of variation in performance contingent on weather. My failure has been brewing for probably 3-4 months before the last real drop happened. Again, this isn't an easy problem, but if you are really down on power this is a great place to start because it's not an isolated problem and there's a good set of guidelines that should help you identify it.

The new part is coming in early next week. I'll be sure to post impressions about it then.

I hope this post was informative, and helps a few of you out there with this problem. Any additional questions, please keep them on this thread and not through PM or email so that others can read the responses and discussion.

Regards,

Marcus

vrus

Hey Marcus,

Sorry to hear about the water pump. I have been suspecting mine for a while now.. My car runs pretty hot.. It is damn quick, but the engine temps rise above 100celcius all the time.

I have a nagging feeling that my car is not far behind yours.. I have an early 2003 build car. It has 49700km (approx 31000miles).. I use autotap regularly and it hasnt brought up any codes that are stored so I guess I am ok for now...

Keep us updated on what happens.. What is your engine temp usually when you are cruising on the highway?

Co 55 AMG

Marcus, What year was your old E55?
Regards.

Edit: outstanding write up.

CynCarvin32

I had the pump fail on my SL55k and I will say it is not something that goes unnoticed. If it fails you will get on the gas and lift but the second you ask for more power the car will be slower than say a Civic EX or a Mustang V6 (both of which pulled on me when the pump failed). Once the car notices high intake temps it seems to retard timing and cut the blower both of which make the car seem like there is a bunny under the hood chasing a carrot!

Once the temps cool down again the car runs as normal so you give it some gas only to see the temps get too high and then the car starts to drag the anchor once again.

You wont see a slow decrease in power... instead its an all or nothing failure. You are just seeing the car get moody with warm weather. All Kompressor AMG's do that... at least every one I have owned.

OZC32AMG

Is it the intercooler water pump you guys are talking about?

medici78

Will it increase indicated coolant temperature on the dash when the pump fails?

Vadim @ evosport

Marcus: I am glad I could help. Good write-up.

Victor: Engine coolant temperatures should not be affected by intercooler circuit. I would check coolant level, you should be in mid90s C.

OZ: Yes, we are reffering to intercooler pump.

vrus

Hi Vadim,

Yup. I know the intercooler circuit doesnt affect the engine temp.. I was only wondering what engine temp Marcus regularly sees on his car to compare against mine. I was wondering if maybe I had a faulty WATER pump. My engine coolant level is pretty good. Reservoir seems at the correct level.

My car runs at 100celcuis most times in stop & go and goes down to 90 - 95 on the highway when I am off boost for a while.

Marcus Frost

Victor,

It's a tough cookie, now with your mods it will be even harder to diagnose because you've increased your baseline and therefore have no reference point. I'd be wary...

Also, more importantly, do *not* rely on your OBDII scanner to pick up any codes from your water pump. These are MB Star Diagnose specific DME codes and not OBDII standard codes. Only STAR will find them...

You are probably due for a B service soon... if that's the case, have them check for any water-pump related codes. You never know what you might find and they don't necessarily just pop-up in STAR either.

My indicated temps were around yours, even a little higher. The amount my temp would drop when I turned on the heat full blast would be almost 40F according to one of my logs... doing that will cool off any car but 40F is getting a bit suspicious. Try that on your car with your scanner... just drive it around, pull into your driveway, and turn the heat all the way up temp wise and full blast. Watch the coolant temp, see if it plummets.

-m

Marcus Frost

Thanks, my old E55 was a 2002.

-m

vrus

Hey Marcus,

On your car, its your INTERCOOLER fluid pump that failed right? Not the car's water pump that circulates the engine coolant?

The posts that Vadim was making and others were making were about the Intercooler fluid pump failing and causing the IATs to skyrocket and turn off the supercharger.

On my car, I am talking about the water pump. I have heard people say that the water pump on these cars is prone to failure also and that is what is worrying me. That's probably why my engine temp is a bit high.

Just want to be clear and make sure I am not misunderstanding.

medici78

So, you're saying that if it plummets, there is likely a failure?

CynCarvin32

I dont know how else to say this BUT I have had 4 kompressor cars and 2 have failed. This item does not get weak and a car will not run warm because of it. It is an electric motor and when it fails to work the pump is done. If it works the car is fine. When it does fail the pump stops and the car will shut the blower off 100% until the normal cooling system can bring temps back in line.

If your car is running warm and slow, have the MAS checked, look at the intake air temp sensor, check the coolant system (usual suspects etc) and look at the wiring harnes (a false reading could cause the car to dial back timing etc).

But if you car is making more than say 250 hp (what happens when the pump fails and the coolant temps get warm) your pump is fine. I would not "worry" about this because the car has so many safety nets to keep you from damaging anything. It turns off the nuclear reactor (I mean blower) well before you will cause any damage.

Your car sounds fine to me just very prone of being sensitive and that sounds like a Kompressor Benz. Enjoy the car!

Vadim @ evosport

Let me see if can clarify it again.

55 kompressor engine, like any other engine out there, has a water pump. It's function is to cool the engine. That is it, it does not have anything to do with kompressor.

It also has another water, "fluid" pump that circulates coolant through kompressor intercooler and heat exhanger to cool intake air temperature charge coming out from kompressor. That is what fails. It is a Bosch pump that fails. Sometime it fails intermittently, sometime it just dies. In either case DME will shut-off kompressor clutch when intake charge temperature exceeds 225F (255F on some earlier E55s). It will turn it back on at 180F.

When kompressor is off. There is no boost. With 9:1 CR and breathing through kompressor, 55 makes 230HP. You will definitely feel it.

DME will store codes for pump failures, however only a shop with STAR diagnostics can read them.

By now most MB dealers should be aware of this problem.

P.S. 55s K do not use MAS, it uses speed density for fuel and spark calculations.

CynCarvin32

things do change with time.. thats a good thing!

my poit was just that the pump failure is something you notice in a big way and not something that simply slows the car down.

thanks for the info

vrus

Vadim,

I think the confusion for most people is the misuse of terminology.

We just need to standardize on the terminology we use when we talk about our cars.. "water pump" should refer to the car's cooling system pump, and "intercooler FLUID pump" should refer to the pump that is used for the intercooler circuit.

regor60

Is there a separate reservoir for the supercharger for the non-modified E55 ?

I'd like to dump in some water wetter if so. Right now, I've put in only in the engine cooling system.

vrus

No. In stock configuration the coolant lines and coolant are shared between the engine and supercharger intercooler. You can put water wetter in there.. I did but I didnt notice any difference in temp to be honest.

regor60

FYI on the Water Wetter, here in Atlanta, I can't remember the last time I saw temps above what looks to be slightly less than 90 C on the temp gauge

OZC32AMG

Hi Guys,

What is "Water Wetter"?

Joe

vraa

http://e30m3performance.com/myths/mo...ter_wetter.htm

It's a antifreeze replacement / add-on I believe.

OZC32AMG

Thanks Rick,

I got it now, it basically reduces the surface tension of water. We use this in the pool industry to remove insects from the pool surface (makes them sink to the bottom of the pool) and to also make the pool water less attractive to Ducks. Ducks do not like water with a low surface tension (must be harder for them to float in) and they don't like suds, so for ducks we make the water frothy on the surface.

It all makes sense now!

Joe

Marcus Frost

Update.

I forgot to follow up on this thread.

The car is definitely faster now, and oddly enough my MPG has risen a few miles as well with the replaced pump. On the work order they noted a new part number for the water pump so I am no longer using the old design one. I do not have a copy of it here at work but I can provide it for anyone who is interested.

Very happy with the results.

-m

anerbe

marcus,

i'm having a hard time getting the dealership to find the problem. it also happens with mine. when the car gets hot, it runs like a passat 1.8t with a blown turbo. it will randomly kick in if I let off the gas for a while.

they took it in with me telling them that the car randomly cuts power when warm. they said it's functioning fine. i'm sure that some random tech tard had the engine cold, did a few 1/4 runs and gave it the "i beat on it and nothing wrong occured" approval.

any tips to get them to look for this problem. also, do you have the updated part number for the pump, as well as the old part number? thanks!

Marcus Frost

Ernie,

I'll post the exact words off the work order for you.

-m