Idling rough on first tank of gas?
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From: San Francisco, CA
1995 Acura
Idling rough on first tank of gas?
My car is so new I haven't had to put gas in it yet. I've noticed that at idle it runs a little rough--nothing severe, just enough to notice that it's not purring smoothly. I'm hoping that a full tank of 91 octane will fix this. Do you suppose the free tank from the dealer was less than super?
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I've been reading that the engine is noisy for the first 30 seconds then the sound smooths out.
I noticed that when I took a test drive on one in Redwood City. Does the idle smooth out? Is it rough as you drive it around town?
I noticed that when I took a test drive on one in Redwood City. Does the idle smooth out? Is it rough as you drive it around town?
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From: Kentucky
2002 C230K
I've never had an issue with this, but I do use 93 octane Chevron non-reformulated gas and have 6K + on the car. Not sure if 93 octane is available for you, and I'm positive you can't get non-reformulated gas in CA.
Reformulated gas has additives (MTBE) that cause it to burn quicker and thus hotter. The thought being this will assist in reducing emissions, and in turn, pollution. You probably already know about MTBE being from CA, but I just mentioned it in case you weren't familiar with what I was talking about.
Reformulated gas has additives (MTBE) that cause it to burn quicker and thus hotter. The thought being this will assist in reducing emissions, and in turn, pollution. You probably already know about MTBE being from CA, but I just mentioned it in case you weren't familiar with what I was talking about.
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From: Gaithersburg, MD
2002 C240 6-spd (ret)
Probably wait and see what happens after you fill up w/ at least 91. It is possible your dealer used 87. You might want to run the tank down most of the way to get rid of whatever's in there.
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From: Lincoln, NE
2000 BMW Z3 2.3 Roadster (hardtop current ly attached)
Re: Idling rough on first tank of gas?
Originally posted by SFVideoGuy
Do you suppose the free tank from the dealer was less than super?
Do you suppose the free tank from the dealer was less than super?
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I find it difficult to believe that a MB dealer would send you off with less than 91 octane. Afterall, all non-diesel MBs in the US use 91 octane, don't they?
Remembering the frantic horror stories on this forum from others who introduced 87-89 octane by mistake, it didn't take long for the system to start throwing fault codes and so forth. I wouldn't think that the dealer would volunteer for such immediate customer disatisfaction.
On the other hand, there have been an equal number of posts from those questioning the inherent roughness of the 2.3L engine.
You have a beautiful car (from the pix in the "delivery" thread). I'm sorry you're having the problem. I suppose it's possible they sent the "new valet guy" to the station to get your gas, and they forgot to tell him what to get. Anything can happen. But it IS printed "PREMIUM FUEL ONLY" on the fuel filler cap.
Remembering the frantic horror stories on this forum from others who introduced 87-89 octane by mistake, it didn't take long for the system to start throwing fault codes and so forth. I wouldn't think that the dealer would volunteer for such immediate customer disatisfaction.
On the other hand, there have been an equal number of posts from those questioning the inherent roughness of the 2.3L engine.
You have a beautiful car (from the pix in the "delivery" thread). I'm sorry you're having the problem. I suppose it's possible they sent the "new valet guy" to the station to get your gas, and they forgot to tell him what to get. Anything can happen. But it IS printed "PREMIUM FUEL ONLY" on the fuel filler cap.
Last edited by MB-BOB; Mar 5, 2002 at 07:23 PM.
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From: Sitting behind thing freakin desk of mine. Dreaming I was playing my Taylors, and driving my Benz. Long Live The VRAA!!!!!!
C230 Sports Coupe
A local gas station was doing a grand opening promotion a couple months ago and i was lucky enough to fill my tank with 100 octane racing gas for 1 dollar a gallon. The car never ran so smooth. I wouldnt recommend it all the time but every month or so if you can find a place that sell racing gas, run your tank down very low, the put a couple gallons of that in it and the fill up with 91/93. see if that helps.
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From: Orlando, FL
2002 Mercedes-Benz C230 Kompressor Sports Coupe
The C230 manual suggests that if you have to put in lower octane gas, you can, but you should not wait to empty the tank. Instead, as soon as you use some of it up, mix-in some higher octane gas. If you are not sure what is in your tank now, put in the highest octane you can get to mix with what is in there now.
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From: Central NJ
C230K Coupe/Orion/C4/C5/CD/AMG Spoiler/V60/TeleAid, 2 MGB's
or....invest a few bucks at a car parts place and get some OCTANE BOOST....
STP, Castrol, Pennzoil all make very good products.
(and just a side note: Cam2 Racing Gas is the only national brand that has "High Octane" gas rated at 98 Octane...so I don't know what they sold Timmy)
STP, Castrol, Pennzoil all make very good products.
(and just a side note: Cam2 Racing Gas is the only national brand that has "High Octane" gas rated at 98 Octane...so I don't know what they sold Timmy)
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From: Lincoln, NE
2000 BMW Z3 2.3 Roadster (hardtop current ly attached)
Originally posted by MB-BOB
I find it difficult to believe that a MB dealer would send you off with less than 91 octane. Afterall, all non-diesel MBs in the US use 91 octane, don't they?
I find it difficult to believe that a MB dealer would send you off with less than 91 octane. Afterall, all non-diesel MBs in the US use 91 octane, don't they?
I actually got reprimanded for putting premium in a $45,000 SAAB... no joke.
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From: Sitting behind thing freakin desk of mine. Dreaming I was playing my Taylors, and driving my Benz. Long Live The VRAA!!!!!!
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[i]
(and just a side note: Cam2 Racing Gas is the only national brand that has "High Octane" gas rated at 98 Octane...so I don't know what they sold Timmy) [/B]
(and just a side note: Cam2 Racing Gas is the only national brand that has "High Octane" gas rated at 98 Octane...so I don't know what they sold Timmy) [/B]
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From: Deerfield Beach, FL
2006 MB C230 SS 6spd, Navi
OK I've lurked your threads SFVideoG*y and up until now i've put up with it, but i'm tired and you whine too much. I love my coupe it has 8K miles in 3 months and it drives better than anything I've ever driven. There is not an ounce of saliva I can spend maligning it. So please stop I can't stand whiners. Just f****** say <B><I> Yes Sir. Thank You Sir for this fine automobile.</I></B> and shut up.
nuff said
in case you're wondering yes I am prior military service.
get on with it slackers, I didn't complain about the features of my HUMMV even though it was made by the lowest bidder.
nuff said
in case you're wondering yes I am prior military service.
get on with it slackers, I didn't complain about the features of my HUMMV even though it was made by the lowest bidder.
Last edited by WyattEarp; Mar 6, 2002 at 02:53 AM.
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From: Gaithersburg, MD
2002 C240 6-spd (ret)
Originally posted by MB-BOB
I find it difficult to believe that a MB dealer would send you off with less than 91 octane. Afterall, all non-diesel MBs in the US use 91 octane, don't they?
I find it difficult to believe that a MB dealer would send you off with less than 91 octane. Afterall, all non-diesel MBs in the US use 91 octane, don't they?
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Originally posted by MarkL
MB-BOB, I have to agree w/ DasMafia. When I bought my Passat, I was given a full tank of gas. That car also "required" 91, and my salesman told me they "only have" 87. They couldn't have cared less...
MB-BOB, I have to agree w/ DasMafia. When I bought my Passat, I was given a full tank of gas. That car also "required" 91, and my salesman told me they "only have" 87. They couldn't have cared less...
HOWEVER...
Previous posts on this less-than-premium theme clearly indicate that mistaken introduction of lesser octane gas in a current production MERCEDES-BENZ almost invariably results in NEAR IMMEDIATE MALFUNCTION CODES from the system. Thus, I wouldn't think it so easy for the dealers to get away with this stunt, given the apparent sensitivity to less than 91 octane.
If MB dealers played like they were Saab/VW dealers on a wholesale basis, I would think every third thread on this forum would be about this subject, since we all would be having malfunction codes or "Check Engine" lights screaming at us within a day or so after delivery. Since this is not the case, I'm concluding that this is a sporadic problem, at worst, meaning that the vast majority of MBs are delivered with 91(+) octane, as intended.
Does that make sense?
Last edited by MB-BOB; Mar 6, 2002 at 02:15 PM.
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From: Dexter, Michigan, USA
2002 C230k
Being a newcomer here I missed the threads mentioned about error codes with lower octane gas. What error codes were they?
I'm sure I read somewhere in the literature that the software can control for knock on each cylinder individually. I'd guess that all it does is back off the timing, and maybe even let up on the throttle under a severe condition? Wouldn't surprise me if that brought up fault codes... but if the system is doing it's job it shouldn't hurt anything. Basically an electronic slap on the wrist. Once the octane is changed it should go back to business as usual.
On a related note I'd be leery of adding octane boosters to anything with an OBDII emissions system. Maybe I'm being overly paranoid here, but not knowing what chemicals are in the booster I wouldn't want them running past the sensors. They're not the most robust parts out there.
I'm sure I read somewhere in the literature that the software can control for knock on each cylinder individually. I'd guess that all it does is back off the timing, and maybe even let up on the throttle under a severe condition? Wouldn't surprise me if that brought up fault codes... but if the system is doing it's job it shouldn't hurt anything. Basically an electronic slap on the wrist. Once the octane is changed it should go back to business as usual.
On a related note I'd be leery of adding octane boosters to anything with an OBDII emissions system. Maybe I'm being overly paranoid here, but not knowing what chemicals are in the booster I wouldn't want them running past the sensors. They're not the most robust parts out there.
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From: San Francisco, CA
1995 Acura
Flaming Wyatt
Yikes Wyatt! Too much caffeine? I think your quote: "yes I am prior military service" pretty much says it all. Nothing against the military--I've got plenty of friends in the service, I just think it's amusing that you use it as an excuse to spew venom and testosterone (to say nothing of bad grammar.) I don't really feel I need to defend what I wrote--for me $32,000 is a lot of money, and I want to make sure that my car is operating normally. My thread about the speed-sensitive volume is a ditto. The whole POINT of this board is for owners and prospective buyers to educate one another about these incredibly complex vehicles. That seems to be lost on you.
I think Alicia Silverstone said it best when she said, "Whatever."
I think Alicia Silverstone said it best when she said, "Whatever."
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From: Southern California, USA
2003 CL55 AMG
Wyatt, let me take this opportunity to remind you that this is a public forum. A forum where everyone's perspective is welcome whether you, anyone else or me agree or disagree with it.
One thing we will not tolerate here are personal attacks on other members.
Enough said.... I think we all get the point.
One thing we will not tolerate here are personal attacks on other members.
Enough said.... I think we all get the point.
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From: Deerfield Beach, FL
2006 MB C230 SS 6spd, Navi
Re: Flaming Wyatt
Originally posted by SFVideoGuy
Yikes Wyatt! Too much caffeine? I think your quote: "yes I am prior military service" pretty much says it all. Nothing against the military--I've got plenty of friends in the service, I just think it's amusing that you use it as an excuse to spew venom and testosterone (to say nothing of bad grammar.) I don't really feel I need to defend what I wrote--for me $32,000 is a lot of money, and I want to make sure that my car is operating normally. My thread about the speed-sensitive volume is a ditto. The whole POINT of this board is for owners and prospective buyers to educate one another about these incredibly complex vehicles. That seems to be lost on you.
I think Alicia Silverstone said it best when she said, "Whatever."
Yikes Wyatt! Too much caffeine? I think your quote: "yes I am prior military service" pretty much says it all. Nothing against the military--I've got plenty of friends in the service, I just think it's amusing that you use it as an excuse to spew venom and testosterone (to say nothing of bad grammar.) I don't really feel I need to defend what I wrote--for me $32,000 is a lot of money, and I want to make sure that my car is operating normally. My thread about the speed-sensitive volume is a ditto. The whole POINT of this board is for owners and prospective buyers to educate one another about these incredibly complex vehicles. That seems to be lost on you.
I think Alicia Silverstone said it best when she said, "Whatever."
I think I'll just go back to lurking. Prior Military Service is in reference to the Sir Yes Sir.
Last edited by WyattEarp; Mar 6, 2002 at 02:18 PM.
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SFVideoGuy, if the rough idling persists with subsequent tanks, you might ask your dealer about this possibility...
https://mbworld.org/forums/showthrea...ghlight=octane
Trying to keep it constructive...
Spyke, I've not experienced this problem myself, but the previoius threads (on the older forum) mentioned the "Check Engine" light as the first sure indication that you have a problem when degraded or lower octane fuels are used. Yes the system tries to compensate, but apparently the light remains on until you introduce good gas... then it eventually goes out.
Of course, the "Check Engine" light can mean several things in addition to bad gas. But on a brand new car, the Teleaid advisors seem to indicate bad gas as the first diagnosis (whether appropriate or not).
https://mbworld.org/forums/showthrea...ghlight=octane
Trying to keep it constructive...
Spyke, I've not experienced this problem myself, but the previoius threads (on the older forum) mentioned the "Check Engine" light as the first sure indication that you have a problem when degraded or lower octane fuels are used. Yes the system tries to compensate, but apparently the light remains on until you introduce good gas... then it eventually goes out.
Of course, the "Check Engine" light can mean several things in addition to bad gas. But on a brand new car, the Teleaid advisors seem to indicate bad gas as the first diagnosis (whether appropriate or not).
Last edited by MB-BOB; Mar 6, 2002 at 02:58 PM.
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From: San Francisco, CA
1995 Acura
Thanks MB-BOB. It's really pretty minor. The idle speed doesn't stay at a constant 750--but it's darn close. It occasionally bounces between 500-1000. It's probably normal. If there was a shred of truth in Wyatt's flame, it was to not sweat the small stuff. I agree.
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From: Portland, OR
2001 CLK320
Rough idling >> possible symptoms
With the surging idle speed (which you shouldn't see at all!) this indicates a couple of potential problems:
defective MAF (Mass Air Flow sensor) or its related electrical harness - this is a common problem on late model cars
or -
a defective coil pack. Since I don't have the 2.3 K engine, I don't know exactly what kind of ignition coils are used in your application...
***
When my car was in for warranty service (different issue than yours) one of my 6 ignition coils died on the technician while they were checking out the symptom I had complained of. My V6 engine uses 12 plugs and a phased-spark ignition.
I got a call from the service advisor asking if I had rough idle symptoms (which I hadn't) and they discovered this, it was found that a coil had failed during their testing.
So - watch this symptom. I haven't heard of anyone else having rough idle/ uneven idle symptoms like that. If it goes on long enough, it can foul the catalytic convertors or the EGR system.
defective MAF (Mass Air Flow sensor) or its related electrical harness - this is a common problem on late model cars
or -
a defective coil pack. Since I don't have the 2.3 K engine, I don't know exactly what kind of ignition coils are used in your application...
***
When my car was in for warranty service (different issue than yours) one of my 6 ignition coils died on the technician while they were checking out the symptom I had complained of. My V6 engine uses 12 plugs and a phased-spark ignition.
I got a call from the service advisor asking if I had rough idle symptoms (which I hadn't) and they discovered this, it was found that a coil had failed during their testing.
So - watch this symptom. I haven't heard of anyone else having rough idle/ uneven idle symptoms like that. If it goes on long enough, it can foul the catalytic convertors or the EGR system.
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From: Columbia, MD
2002 C230K Sport Coupe M6 C5 desert silver
I've stayed quiet on this debate but it seems to me that it would be worth having the dealer check out the car. I have a C230K with 3500 or so mi and that engine purrs with no roughness whatsoever, even during breakin. As an example of how smooth that engine is, this morning on my way in I turned off the climate system for the first time as we are in a warm spell. Usually there is fan noise. The engine was running so smooth and quiet at a stop light that I thought for a moment that it had stalled. The three demo cars I test drove also were incredibly smooth. If you are running rough something unusual is going on. Have the dealer check it out. I can't believe that a dealer put the wrong octane gas in it to save $1.60.
