bbirdwell

For those who had or will have the fuel tank replaced in their car, verify the fuel pump adapter cable is installed!

Been going back and forth with another member of the forum having issues with the fuel supply. Fuel tank replaced under warranty. He sent me a photo of the top of the fuel pumps and the adapter cable was missing. This now makes two confirmed instances (BoostedAero and this other forum member) where the fuel tank was replaced but the adapter cable was not installed. Easy mistake to make as the connector on the original harness matches the new fuel pump connector. The problem is the original harness in the car has power (striped wires) on pins 1 & 3. The new fuel pumps provided with the tank have power on pins 2 & 3. The adapter harness swaps the connections. If you do not use the adapter harness, one of the pumps runs backwards, fuel pressure will drop at wide-open throttle and high rpms, potentially lean air:fuel mixture with chance of detonation and damaged/destroyed engine. The adapter cable is a must with fuel pump P/N 211-470-00-00. You can read the part number on the top of the fuel pump.

See attached photo to see how to confirm installation. Remove rear seat, open the lid over the fuel pumps on the right-hand side. Also, look to see if the foam insulator was installed on the underside of the metal lid; that is intended to prevent the power wires to the fuel pumps from shorting out against the underside of the metal lid.

hayseed

iTrader: (2)

thanks for the details on this and your other fixes for fuel pump relays/fuses ,, I am going to have to do some work now that the weather is starting to cool down - you may never have know that this was messed up until its too late and done some major damage

builtbyfood

This is an issue I am dealing with now. I will go in to more detail later, but if your harness was not replaced, bring it to the dealer and have them replace and make sure the tech who worked on your car gets written up for not replacing parts when they should have. This issue will cause the pumps to run AGAINST each other during higher rpms, 1 pump will feed the rail and the second pump will pull away from the rail and cause the #8 cyl to starve.

Doug427

Does anyone have a part number on the proper adapter cable?

bbirdwell

211-540-07-00. About $15.

hachiroku

https://login.i.daimler.com/internet...and=aftersales

http://aftersales.mercedes-benz.com

how do we sign up...it seems if you have a classic Benz you are given free access after registering for the Mercedes Car Club and it is free of charge.

Fountain35

Is the wire harness adapter the same for all year e55's 2003-2206?

Fountain35

The dealer supposedly changed my pumps but I smell fuel after a fill up so I'm going to pull my back seat and take a look.

tw2

For the pumps yes I believe so. For the sender side, yes but it is dependent on the type of sender assembly your car has, there are two different versions. Check if you already have a pump harness installed. They are about 2ft long. If so, someone has definitely been in there.

Fountain35

The work orders describe "RAP Program" and "fuel tank leaks". So I am not sure what they did. It shows work code # 0 47001 04 7

T9ja

Thanks for this info. I'll have to look into that, because I think I'm going through similar problems. Each time I go WOT, it feels like the pressure drops, it sounds like a rushing sound coming underneath the car, and it happens every time I go WOT, mostly from a stand still. I replaced the fuel/tank system too over a year ago.

Doug427

Just got my car back from the dealer for the extended warranty fuel tank replacement. I haven't got a chance yet to pull the back seat and check, but the work order clearly lists two "cable harness" - 211-440-05-07 and 211-440-55-08.

eFifty5AMG

Just got mine back from the dealership today WITHOUT the adapter extension installed. New 211-470-00-00 fuel pump installed with the old factory connector. Thanks for bringing this to light; I never would have known.

tw2

Yep, they still run and appear to drive fine but one pump spins backwards and the engine runs lean. Definitely not good with your mods. Check your fuel pressure under WOT.

SilverE5588

Interesting , thanks for the insight. Had the tank done on my 05 at the end of last year - going to check this tomorrow as well as the repair order .

bbirdwell

Amperage with one pump reversed polarity:



Amperage with both pumps correct polarity:

Fountain35

I need to bring mine in, dealer says bring it down. It will be interesting to see what Doug finds. It's hard to believe dealers can screw this up. This isn't a difficult job..

Thanks bbirdwell for the thread and heads up.

SilverE5588

Yeah there is a tech note on the bottom of my fuel tank workorder . Tech states - also replaced wire harness' with 211 540 07 00 and 211 440 05 07 . Also the pump billed on mine was 211-470-03-00 is that the revised pump ?

Fountain35

How do you pull the rear seat on the car?

tw2

Two small metal clips to push at the front under the seat. Easy once you feel around for them. Then just lifts out.

Fountain35

Thanks!

T9ja

Can you tell if this is the right connector?

tw2

As far as I know there is only one version which you have.

bbirdwell

You have the adapter cable installed. It's the one wrapped around your fuel pump lid. You can confirm the wires on pins 1 and 3 of the end of the adapter cable attached to the OEM harness (the one outside the cover) are swapped to pins 2 and 3 on the connector attached to the fuel pumps. It's easier to install the adapter cable rather than swapping the pins in the connector.

T9ja

Thanks.