I'm getting ready to purchase my first MB and have had a hard time deciding if I wanted a 600, or if I wanted to fork up the extra money for a 65. I decided on the 65 and have been in negotiations with a local dealer on an '06 with about 30k miles. We're agreed on price but there's one major hick-up.....the car seems to be underpowered.

I drove the car for the first time a few days ago with the salesman and my brother (who owns a stock S600) in the back seat. After a few short blasts I turned to my brother in the back seat and said "this things a turd"- to which he and the salesman fully agreed. It felt significantly slower than my brothers 600....it wouldn't even break the tires loose from a dead stop.

After suggesting to the dealer that maybe the intercooler pump was bad and other various possibilites they told me that they had just replaced the pump and assured me that was not the problem.....and that the "computer had been completely reset during the install and the car needs to re-learn the driving habits of the driver"...they assured me that over time the performance would improve. My brother and I both agreed that car needed about 100-130hp to make it right. I left empty handed and told them to call me when they found out what was wrong.

The salesman calls me 24hrs later and tells me he drove the car all day and it's "much better....night and day difference"....and that they changed nothing, just drove it. So, this morning I went for another test drive and indeed it WAS much better.....I'd say a 50-60% improvement since the day prior. So, just to be sure, my brother and I lined up his stock 600 next to me in the 65 (with the salesman riding shotgun with me) on a feeder road and got after it.....my brother pulled me both times. Not real bad, but he was definitely walking off on me. Once was from a 20-25mph punch and the other was 40-45- on both occassions I got my a** handed to me . The salesman was just as surprised.

We returned to the dealership and the head-tech says it's a combination of 2 things........low octane/bad gas (the car has been for sale for about 75 days and came from California where octane is as low as 85) and the ECU hasn't fully "re-learned" or adjusted for the drivers habits yet.

So, my questions are;

a) In a real world race (no magazine articles, etc) how bad should a stock '06 65 walk off on a stock '04 600....all else being equal.

b) Is it possible that bad gas (or low octane) and a computer that's been "reflashed" or "reset" would cause such a loss of power? Originally, I didn't think so- but after driving the car 24hrs later it DID improve substantially....I was very surprised.

c) If I drive the car aggressively will it slowly improve over time??


I guess what I'm worried about is going back next week, racing my brother and staying side-by-side with him? If that's the case, I'll buy a 600. The sole reason I'm looking at the 65 is becuase I want to be the fasted sedan on the road. I was always under the impression that the 65 would be .04-.05 faster than the 600 on the strip and would have no problem walking off on one from a roll. Am I wrong??

Thanks in advance for any feedback.....

-Busa196-

 

Great Story, Let your brother drive the 65 and you the 600, to make sure its not driver error.

Yea, I can beilive its the ECU reset. My dealer did something to my ECU and the car is re-learning my driving habits...Really annyoing lol. But one can never be sure. Let them fill the car with 93 octane I guess, Its not going anywhere alrdy 75 days in the dealership.

Yes the 65 should walk the 600.

 

I want to race a properly working S65 AMG...

 

Gas is a good possibility. Siphon it dry and fill it up with premium.

 

One of the sales managers is going to drive it over the weekend to burn the remaining 1/2 tank of gas.....He'll put some fresh 93 in it and we'll see what happens Monday. I'm just curious if in a perfect world if I should be walking away from a stock 600....and it sound like I should be.

As far as driver error is concerned, we we're both in 1st and in Sport mode.....after that it's just a matter of mashing the "go pedal"....not much to mess up there. And, after we were into it for 2-3 seconds he was still walking away from me....it wasn't just the "jump" but rather the continous pull that caused concern.

Thanks for the feedback gents- any more comments welcomed

 

Are you dealing with an MB dealership? If not since its an 06 and still under factory warranty have it it inspected at a MB dealership prior to purchase

 

if you love the car get a buy back clause in the contract stating that you have 5 days and 500 miles to determine satisfaction,if you dont like it you should only lose $500 and walk away.i have used this policy on all our cpo MB's.stop letting the help drive your next dream car and go get it.

 

both nice cars mate

 

ECU tune on the 65= 750 hp/1000 TQ around there rofl

 

Yep, a local MB dealership- and, if I decide to purchase the car I'm paying a bit extra to have it CPO'd. They've ran all the tests they can and tell me there's absolutely nothing wrong with the car...."it just needs to be driven"


I actually tried that yesterday before leaving the dealership. I told them if they were so certain it just needs to be driven witih some fresh gas in it, let me buy it witih some kind of "return policy".....he literally said "there's no way I can do that."

 

That still sounds so crazy to me. I actually would suggest you not buy that S65. Let's be real here...stock vs stock - that S65 should have left the S600 behind, especially at the 25 - 45 run. EVEN with cheaper gas, and EVEN with a reflashed ECU.

Bottom line is you have a lot more torque, a lot more BHP, and theres absolutely no excuse for it to feel SLOWER (TURD) on your first run.

I actually was anticipating you saying you asked to pop the hood and found a 550 engine inside and the car was really a poser.

 

BS.. Bs.. and more Bs...

I agree with Chucky300..


IF they had ran all of the test then you would not be haing htis conversation right? Another reason I know CPO's is a joke...

IF a dealer cant even give you 5 days for buyers.. remorse or whatever.. I wouldn't buy a car from him.. Most of the time you have at least 3 days if you change your mind....

Just go find a car somewhere else We're not talking about some rare find here...

 

I do not remember the exact days/miles allowed because my S500 was very nice and this was not an issue but part of the CPO warranty was a 5 day / 500 mile, no questions asked return policy. That was posted on a MB CPO poster in the sales area.

 

bmurphywa, you're right. I just recently bought a CPO'ed S500. Part of the CPO warranty is a 5 day / 500 miles no questions asked return policy. Additionally, if you buy from a dealership, there should normally be a 3 day / 300 miles offer to return the car, even if it is not CPO'ed...

...I still have the car

 

wow...these are suprising results but I can bet that you need to give the 65 a chance. I have not had a chance to run a 65 series car but I would have to say that they would have to be .2/2mph faster than a 600 just due to sheer cubic inches. I know that a similar S65 with the Renntech tune as I have ran 11.0x@128 with renntech ECU/TCU and drag radials only. My best after the same ECU tune was 11.27@121.88 so you can see that the 65 has the potential to run much faster than a 600 with similar mods. Of course it is possible that you were driving a true turd and nothing will make it run better but that is highly unlikely. Get the 91/93 octane in the thing and redo your previous test with your brother and see what happens.

 

Update

My brother (“housclass” on this forum) and I had a chance to go back to the dealership yesterday and drive the 65 with some fresh gas. I actually let the salesman drive it while my brother and I were in the 600- I wanted no excuses if the 600 walked off on the 65 again.

After 3 blasts down the feeder road from a 25mph punch, the 65 walked away every time- but, it was by no means a “slaughter”. I’d say by the time we were at 120ish (no worries folks, private MB test facility) the 65 was 1.5 cars ahead?? Maybe my brother will chime in. This was the 3rd time we had test driven the car and it got noticeably faster each time. I’m now the proud owner of an ’06, CPO'd, Flint Gray S65 that gets a 9 of 10 in it's overall condition. After the 40 mile drive home and some short romp sessions I swear the car felt better by the time I got home. I have no doubt that after a week or two of me piloting her, she’ll be 100%.

What I’ve learned from this;

-What they say about the computer having to “learn” the habits of the driver are absolutely, positively true. I believe you have to drive it like you stole it if you want the car to perform like it’s supposed to.

-My brothers S600 friggin flies- for the very reason mentioned above. He drives his car hard everyday and I think that’s conducive to the way it performs. I’ll bet 600 for 600 his car would have a fairly significant advantage over the average grocery getter- and even a conservatively driven 65 as we’ve demonstrated.


Special thanks to my bro for showing me the ropes and guiding me to the world’s finest luxury sedan, IMO- and for making the continued trips to the dealership to act as a test dummy. Without him, his car, and a willing sales person to act as John Force this sale would not have happened.

I’ll post some pics later. Many thanks to all of you that chimed in.

-Busa196-

 

Congratulations. Yes, these cars need to be pushed if want their true potential revealed. That also means spending dramatically more at the pump, but most AMG owners wouldn't care

The healthiest MBs are those driven frequently, driven hard, but religiously maintained.

 

Congrats to my brother. I'm five years older than him and feel like we have taken the same paths when it comes to hot rods! i started with a 84 grand national and after 20 cars i'm working on my 4th benz. While my brother was wrenching on his c6 supercharged vette (it was a bad azz car...599 to the rear tire) i told him...you reach a point in your life when you don't want to wrench anymore...you just want a fast, dependable car under warranty...imo the v12 s-class is the answer for people over 6' tall. i'll let jason post the good pic's but here's a teaser pic...

btw...the 65 was walking me good...amazing how driving a car hard can make such a HUGE difference!!!

 

Ah, I didn't know that was the car. I saw it last week when I was dropping the car in for service.

 

still retains that "MB decadance" of a black car but without the upkeep of black.that car looks flawless.these cars are like rolling karma,just driving them will produce more prosperity if it is focused correctly.Good on you!

 

Yep, driving it fixes it. My car is back to normal with now even more power than ever hehehe.

 

That's one of my favorite colors in the S65. I was looking at one with the stone interior vs black. Black interiors are so darn hot in the summer. Get that thing to the track for some stock S65 runs. There are so few of these cars that actually get to the track.

 

Flint Grey!(?) I love that color.

I love the rear end of the W220.