[BRN9121]

Hi guys

I just picked up my car a few days ago and immediately noticed a light rough idle. I took her in today and they checked her up fully, no faults.

The service advisor tells me it's due to bad fuel and added an additive, asked me to drive her a little more and this should go away.

This isn't my first performance sedan, so I know something is not normal here. The car has 40 miles on it since driving her out of the showroom.

My E60 M5 and 997 PDK didn't have this issue. I know the 997 was DFI and my E60 was not. But this is the first time I see this on a brand spanking new car.

Any thoughts?

 

[2000 C280 Sport]

Very odd. It is possible and even most likely you have bad fuel. If you dont mind me what octane are you running? What type of additive did they put in and how much?

 

[BRN9121]

Very odd. It is possible and even most likely you have bad fuel. If you dont mind me what octane are you running? What type of additive did they put in and how much?

We are running 95RON ( European Standard rating ). The service advisor did show me the little container of addictive, but I wasn't paying attention and so don't remember what it was exactly.

If this continues, I'm taking her back becuase none of my previous cars idles like this.

 

[siglo]

The additive is probably Mercedes Keropur. It is made by another company and re-badged by Mercedes. Just google "Mercedes keropur additive" and you'll get a lot of info.

I use it with every tank on my G55 & C63 Black Series. Even though my cars are supposed to be GCC standard, the engines, fuel & exhaust are still somewhat Euro4/5 standard AFAIK. Some other car manufacturers do tune (or de-tune) their performance engines to our bad fuel but mercedes amongst others aren't doing that for environmental reasons.

The fuel we have in the GCC does not live up to Euro standard, I am sure about Kuwait at least. In Kuwait, we do have Euro 4 Gasoline but it is only available in 3 stations. I use it sometimes when I don't have a can of Keropur handy but it's 4 times more expensive than the ultra premium and the location of the stations are not very convenient.

I doubt the Mumtaz fuel in Bahrain lives up to Euro 4 standard. You might want to do a little more research before deciding what is the best course of action for you. Other Mercedes cars in my house hold and with some of my friends have had their fuel pump and even valves clogged because they don't use any fuel additive. This will be less apparent to drivers who drive a bit aggressively and tend to reach the higher rev levels of their engine frequently.

My G55 is a 2009 and the fuel pump is fine so far. My friend who has a 2010 G55 replaced his fuel pump during the first 6 months because he did not use any fuel additive and drives like a grand mother.

I hope this helps and keep us updated

 

[BRN9121]

Thank you so much for the insight bro.

It was a surprise to me because I have owned these types of cars before and the ECU (DME) adapt to the furl and correct timing accordingly causing loss in performance, but never thought it would affect drivability of the car.

Also, I believe my car is has an EFI engine and not Direct Injection! I also understand that our gas have sulfur content which has not been removed. This causes injectors to block.

My E39 and E60 M5's were good on this gas and performed even better with 97RON. My 2009 997 was DFI and didn't have this issue either.

Confused but hopeful that after a few hundred kilomters, things should smoothen out!

 

[siglo]

You are most welcome

I noticed you said that you use 97 RON and started wondering what are the RON ratings for the Jayyed and Mumtaz fuel in Bahrain? I am thinking about driving to Bahrain in the c63 to take it around the track. I was planing to use mumtaz fuel with the keropur additive. Is there a third kind of fuel in Bahrain's stations that I don't know about?

 

[BRN9121]

Yes, from time to time, especially during the cool winter months, I treat my cars to VP100 (aka StreetBlaze 100) cocktail drinks! They sell them very close to my home so it's convenient for me.

Salmabad Petrol station also sells Torco Fuels. Splash and dash style.