caliboy

Hey guys,
Just had the strangest thing happen the past couple weeks. I go to start the car cold, I guess, from sitting overnight and I have noticed that the car sparks up, but feels as if it did not catch on and starts mild shaking as if it will turn off. I shut it off and start it up again and vualla! problem gone. No problems driving no problems rest of the day. Until next day and start up from cold again and it does it again. It has happened three times in past month and I think my dad mentioned something as well. Anyone experience this, it's weird.
There are two theories I have:
1) I left the back roof light on with the car off for about 2-3 hours one day about three weeks ago.... possible battery, but that's not enough time or is it?
2) I also made a modification a while back about 2 months ago that makes the emblem on my cl style sport grill light up blue at night. Lights are blue low voltage led type lights and give a nice blue glow from the inside of the emblem only without showing the leds. I turn many heads with that mod..... been meaning to post pics, but too lazy to go at night and do it. Anyway.... these lights are low voltage..... place was very professional when installing and they are just connected with a resistor to blink intermittently at night and turn on when I put my fog lights on. Again-- Could this have affected the battery? They are very low voltage and are made for this, but is it possible MB battery could be affected that quickly or be affected at all?

Capt Nemo o2

I had that same problem a few times and I didnt do either 1 or 2. Almost stalled, had to give some gas to get it to run.

Tejas

I've had the same issue with my 2002 c230K. Multiple trips to the shop, lots of diagnostics . . .

They finally came back and said stop using cheap premium gas!

I've stopped buying Beacon gas and gone back to Chevron, and the problem has gone away.

caliboy

Interesting guys........ I did not think about the gas quality I was using. I have been using plus or midddle octane at the cheapest place I could find cause the gas prices are so ridiculous lately. I'll definitely try that for this next month and see how it goes.

caliboy

Does it still happen to you too or did you change something as well that made it go away? I will definitely try changing the gas I use.

neilsam

Hmmm... I have the same problem BUT..... I only use Mobil Premium (92 or 93 octane).

Going for a tire rotation next week and will ask about it.

caliboy

[QUOTE=neilsam]Hmmm... I have the same problem BUT..... I only use Mobil Premium (92 or 93 octane).



Wow you have the same problem and use only premium gas...... Then it isn't the gas dammnnnn I think I'm going to see if I take it in to get that checked out. I did not expect people to have this problem on such a new car, but I'm relieved I'm not alone. Not that this is great or anything. Just pretty annoying.

jedcred

It can't be the rear light as the car's computer usually shuts off all lights (even those switched on) after about 15 min. It could be you have a short in your new grille light, but I would put more money on something in the fuel system. Have them check fuel pressure from cold start, or it could be something in the fuel filter. There is an off chance that you have faulty spark plugs, but it's not likely.

caliboy

thank's for the tip....... I think I will have them check the fuel system. DO you think they will say anything warranty related for the grille light?

jedcred

Depends on the dealership. If there are wires running everywhere in the engine compartment, however, they may have something to say about that. But be safe in the knowledge that they have to prove something caused a void of their warranty: they cannot simply say "We're not servicing your car anymore, so there!" My advice to you is, don't draw attention to anything you've added; let them come to the realization themselves. Just say, this is happening, someone suggested this idea and that idea, say nothing about the grille light, and see what they say. The tricky part about all this is usually you're talking to an SA who knows little about what you are talking about; he'll just mark it up on the sheet and send it to the mechanic. Good luck to you.

Capt Nemo o2

I did nothing to solve the problem... The last time it happened was this weekend... I only use 93 octane gas, but its quality may be questionable. Its definately not a problem with the sations tank, they move so much gas nothing is in there long enough (the truck comes to fill up like once a week)... I try to exercise my car at least once a day to blow off any carbon that builds up on the spark plug just as a safe guard, and of course because its fun! But if there is a carbon build up problem it could cause this symptom as it would foul the plugs causing a poor spark. MB im sure designed the engine to take crap gas so I cant imagine it being a fuel source only problem. If you use cheap gas and make frequent short trips where the engine doesnt warm to op. temp, in stop and go traffic all the time, or try to accelerate too fast in too high of a gear (lugging) these are all things that cause carbon build up that can foul the plugs.

Also check to see if you are burning oil, that can also foul the plugs... (I think that may be part of my problem, have 7600 miles and needed to add 1qt twice)

caliboy

Already one step ahead of you lol I thought the same thing I'll just go up there like this is my problem please fix it. Thanks man.

caliboy

i 'll check the oil, but I doubt it. As my car only has only about 4k on it. But you never know. About that carbon build up should I suggest it or would they be smart enough to check this?

Capt Nemo o2

I would tell them you heard there was a SB out because of the carbon build up and ask them to just pull out the plugs and check them just to be safe. You can check that yourself if you want to save time.

Moviela

This sounds like bad gasoline. Premium fuel is expensive to make in California, many times more than the 20 odd cents extra per gallon, for this reason some dealers will cheat. Sometimes they will drop regular in the premium tank, other times they will buy fuel from a distributor not authorized by their branding (Shell, Chevron, ect) without the anti-knock or detergent additives specified by the brand. They will put methonol or other cheap organic compounds with a Reid vapor presssure greater than 4.

Try buying from a refiner owned station. they can be hard to find, because the majors (Shell, Chevron, Mobil, BP (ARCO)) only own about 10% of their stations.

Since snacks account for most of the profit at gas stations, owners are trying every trick to increase the take on gas.

Since prices have risen so fast, many people who used to buy premium have stopped, and the premium fuel is getting stale at some stations. Stale gas can have octane as low as 75 as the long chain hydrocarbons break into their smaller cousins. In 1984 50% of gas sold was premium, compared with 8 % today.

I'd suggest a few tanks of Chevron to see if that cures your problem.

Outland

All cars, early in there lives, consume more oil than they do after say, 10K miles. This is due to seating of the rings, wear in, etc.. If consumption continues, then you have a problem.

The quality of all gas brands is questionable these days. It all comes out of the same tank, its just the bottle of additives that makes the difference in brands when they put it in the tanker truck. Some refiners, gas chains and shippers have been getting cheap, saying they put it in, and didn't, putting less in, etc... This has been documented. Do a search of the Milwauke Journal Setinel. They joined up with the EPA and state gov to do a study on fuel quality after a rash of injector failures spread across the state. The additives DO keep your fuel injectors clean.

BTW, running low octane fuel on a boosted motor will bring on mild detonation, especially in the overboosted M271 on a hot day. This will cause the knock sensors to dial back the timing, if they catch it. Something to think about. The motors were designed with premium in mind.