jpohl402

So 60% of the time when I get on the gas, the engine pings terribly because the timing is retarded. Have talked w service advisors at Mercedes dealers in different states, they say this is a common issue - sounds like marbles rolling around in a tin can. This is due to the fact I can only run 91 octane, instead of recommended 95. Tried octane booster and it does improve the problem. Friend of mine recommended Toluene (at Ace next to Lacquer Thinner), said he uses it in a Turbo racecar running like 30 pounds of boost. Any experience ??

gonzales25

I run 91 octane in mine most of the time because 93 is hard to come by in my city. I have never had any pinging problems it has to be another issue. Do you have an ecu tune that requires you to use 93octane?

i_am_amused

+1

91 octane should be fine unless your engine is tuned/modded for increased compression

jpohl402

Sure don't have a tune, factory !
A blind person would think it is an old piece of sh*t, but those of us that can see realize it is a two-year old Mercedes !
Hmm

bbearden

Your engine would not ping because the timing is retarded. Pinging is audible indication of detonation occurring. While tolulene is an excellent octane booster, I'm not sure what the correct stoichiometric ratio is for mixing with gasoline to achieve a desired octane level. Can your dealer check to verify that the kock sensors in your motor are correctly pulling timing out at the first indication of detonation? That'd be my first course of action.

IndiumGreyE63

wow...I've never had a pinging problem. I only have 91 available in my area.

I did have that problem once in a while though when I had my '07 E550. But this '08 E63 has had no issues.

MB_Forever

For reference, my car is 100% stock, and although I try to run 93 whenever possible, I don't hear any detonation when running 91 even when the car is run hard at the track Ideally, the ECU is supposed to sense the detonation and adjust timing accordingly (within range of course). I recommend having the car checked out at another dealership.

AMS Performance

Something is not right, your car should not be pinging (unless your knock sensors are bad or something). Toluene will help and may be a good way to test/diagnose to see if that is in fact the problem. Run 1-2 gallons per gas tank and see if that helps.

Even with 91 octane the benz ECU is designed to pull as much timing necessary to prevent detonation (and you'd be surprised just how much timing it can actually pull to protect the motor), so something is clearly not right.

jpohl402

Thanks for the replies guys-
I will have it looked at.

LB63

I agree, I've been running 91 without problem. The only time I had pinging was when I changed my airfilters and did not completely seal the airbox. The rubber seal was pinched near the throttle body and it was very hard to notice.

Once I properly seated the filters and closed it correctly the pinging was gone and never returned.

jpohl402

So need to have dealership verify that knock sensors are correctly pulling timing ? Does the dealership do this w STAR ?
Thanks in advance...

hcetzneb

Are you sure you are hearing PINGING or maybe something eles.. Let say you were hearing pinging.. with a ping that loud you would be getting some sort of misfire code stored or current. The engine me-sfi unit is a very sensitive unit if the engine knocks or detonates it will store something... or other senario is that the knock sensors are bad .. you would definatley get a cel... if im not mistaking i think with both cases the me would got in to safe mode so are you sure you have a pinging problem??

bobbyfali

I used to run toluene in my Supra: 2 parts 94 octane pump and 1 part toluene = 100octane

To help answer your questions this is how you calculate your octane: Toluene = 114 OCTANE,

(40L * 94octane) + (20L * 114toluene octane) / 60L = 100.67 octane

If you run more then 30% toluene your car might take a little more turns to start. At 30%+ toluene, being it takes longer to burn (the reason for higher octane and why it prevents detonation), hence why it might take a couple more rotations to fire up. If you run 25% & less you should not notice any real difference then standard pump other then more power (if your car needs the octane)! Early F1 cars (yes the 1.5L turbocharged 73psi 1500bhp / 1000hp per Liter BEAST) used to run up to 80% straight toluene but had heaters in their fuel tanks to warm it up.

Like others have already stated your issue CAN NOT be running 91octane causing this sound. 91 Octane is what these cars were tuned for from the factory to run in North America. Something else is going on.

Thanks

Bobby Ali

ba

jpohl402

So, out of one of four dealerships my car usually goes to -
they all seem to charge me for diagnosis they can't prove, therefore nothing gets fixed and I pay for the labor on the "tests"...

The car is out of warranty,
will I have to pay to have them look at the "knock sensors correctly pulling timing verified" or will that be covered ?
Thanks in advance.

2003 S600

If out of warranty of course you have to pay, why would you not have to?

AMS Performance

JP, I know this hasn't been addressed yet... but what BRAND gasoline are you using. Our benzes can be very sensitive to certain brands of gas dependent on the refineries & etc. The Benz dealerships almost always recommend Chevron as they are pretty much the highest quality gas. There are many cases where people were using lower quality fuels (Valero & etc) and had running problems due to our very picky ECUs. This may alleviate the problem. Just a thought

guysandiego

maybe its a lemon -- you better bring it to the dealership and get your complaints noted -- just in case

jpohl402

Thanks for the thought about gas.
On that note, I don't only run one brand of gasoline. I usually wait until the tank is damn near empty, then refill at the closest station. This has included about everything from Chevron to Shell, Texaco, BP Amoco's 92 Ultimate or whatever....
This pinging problem has gone on for the last two years (since getting this car) - steady & persistant - but seems to get progressively worse/more frequent lately.

Thanks !

AMS Performance

If your dealership is not being cooperative, try another MB authorized dealer. It that doesn't work you may want to think about contacting corporate headquarters, or even Germany if need be, that should NOT be happening on such an expensive car.

guysandiego

i said it before - say it again -- You really need to be on top of this-- if you have the paper trail and can show the problem has not been fixed the whole time -- you may have a lemon case ---

AMS Performance

correct

jpohl402

Thanks gentlemen. I will be making some phone calls in the A.M....

i_am_amused

two years? wtf?

you are far more patient than I would have been. I had a problem with a CPO passat and got no satisfaction after ONE trip to the dealer, so I did a little detective work, figured out the email address of the president of VW north america (that was easier than you might think), dropped him a line, and within 24 hours I got a *call* from the head of north american sales. problem solved, and a VW hater converted back to VW lover.

jpohl402

A service advisor at a Mercedes dealer that I was recommended to, contacted a lead AMG technician for the United States, and he thought the problem was likely caused by a carbon buildup (I realize AMGs run rich in fuel, but this one seems to run very rich, exhaust tips are covered in soot immediately after cleaning).... soo... I am going to drive the gas out of tank, add Chevron Techron fuel additive, fill her full, and drive around for 15 mins at around 4000 rpms or so, in an attempt to "clean out" the system...
I will keep you posted...

bbearden

No kidding. After two years of potential detonation, I sure hope the bearings in his engine don't look like hammered s&$#! I'm hoping it is something else for his sake as that engine has taking a beating otherwise.