richardza

Hi guys,

I wonder if anyone can point me in the right direction because my dealership has no idea

My 2007 S600 seems to be running exceptionally slow and has been for quite some time (dealership said it could be a temporary fuel issue). It almost feels like it's pulling off in 2nd gear (I've checked this and it's not). It used to wheel spin constantly under hard acceleration and now it just feels limp. A friend in his VW golf GTI made me look like I was in reverse when we were testing acceleration.

Any ideas?

Thanks

MonroeHandyMan

Maybe bad fuel, clogged fuel filter or injector. Do you generally get your gas from the same station? Are you using Premium? Try a fuel additive like Techron. Cant hurt...

DaveW68

Mine has felt slower than normal recently too. I have a feeling that it's because I've been using Sam's Club gas since I've had the car, which I've found out doesn't have enough detergents to properly keep your fuel system clean. I just filled up with Shell premium last week (who claims that their gas will clean out 60% of the crud buildup from substandard gas in just 1 tankful, so we'll see if that helps at all.


The summer blends of gas have power robbing additives, and the summer heat is likely lowering power output as the turbos won't stay as cool.


There is a service that many places offer called "Motorvac" which is supposed to make your cylinders, pistons, intake, fuel rails, fuel injectors, and anywhere else the gas goes pristinely clean after 1 service....and helps restore compression to the proper levels. My local mechanic charges $130 for the service, so I'm strongly thinking about having it done to see if it helps.

alx

couple things need to be done if no codes are presented.

1. have your intercooler pump checked - most likely it is probably dead and they normally do not throw codes of any kind.

2. reset ecu/ tcu adaptations via star/ das

3. have boost levels/ proper wastegates operation confirmed via star/ das.

but... it is most likely your intercooler pump

WHPH28

If it's the intercooler pump, you might as well upgrade it instead of going with a stock one especially since they are so cheap.

alx

The stock upgraded pump is every bit as good as any of the aftermarkets.

WHPH28

I didnt know there was a stock upgraded one. I see other that claim they flow 50% more.

alx

Yes. The upgraded Bosch pump part number ends with 10 if I a remember correctly.

WHPH28

I will have to check it out. Thanks!

Speedriven1

I second intercooler pump. Even if it ticks on when you put power to it, when they fail they'll still come "on", but just won't push any fluid through. The good news is a solid upgrade is like, $500 (from us, anyway) and isn't that much more expensive than the stock unit.

Speedriven1

It's not just flow, it's head pressure. Stock is something like 0.3 bar, and the unit we use (a Pierburg with a machined head) is over 1.0 bar.

wilassasin

Get some techron fuel treatment if you think it's bad fuel.

ima55r2

If you haven't done some spirited driving lately and you have an adaptive transmission, the car might have gone into granny mode to save gas. You can either drive and stomp on the gas 4 or 5 times in succession or do a reset of the ECU doing the instructions in this thread. https://mbworld.org/forums/w211-amg/...set-works.html It did work on my E55 and my S550 when I tried it.

richardza

Thanks for all the replies!

I consistently only use the best possible fuel from one brand with all my other cars and never had an issue so I'm pretty sure fuel isn't the issue.

I did the TCU reset which was great for throttle response but the power just wasn't there.

I'm now fairly convinced it's the intercooler pump - booked it in for Thursday and will let you all know the outcome. Holding thumbs!!!

Can't wait to have the power back and then continue with a few subtle power mods :P

T.H.Carrera

so was it the intercooler pump ?