My 2005 crossfire that I just bought is running a bit rough (there is a slight, but distinct vibration) when stopped in gear at lights, stop signs, etc. Dealer says this is normal 'high performance engine' they say. I have a 1998 Yukon that seems to do the same. Something tells me the Germans who made this engine would take this as a personal insult that a 150,000 mile truck engine and a 20,000 MB engine should even be mentioned in the same sentence.

Anyone else have this issue? Is this an issue? The engine sounds ok, I just expected it to be extra smooth all the time.

 

Mine occasionally idles with a slight vibration, and it has 800 miles.

When mine vibrates it doesn't make any noise. The car just shakes a little bit. It always goes away within 5-10 seconds.

 

Mine does a lil shimmy now and then. I'm thinkin time to clean the injectors +50K miles !
Anyone use the add to your tank stuff to clean out the injectors ???

 

Mine a a distinct vibration also.. sporadically at idle at lights. And it only has 650 miles on it.. I beleive this is normal..

 

I have the very same type of problem. Engine at idle...like at lights...just stumbles for a second, almost like something turns on and loads down the engine for a second. I've had it since new and now have 11,000 miles...but still have the same problem. I've tried different make gases, and that does not help. The idle is set about 500 rpm...i wish it was set at 550-600 rpm. Does everyone's crossfire idle at 500 rpm? I was told that this can not be changed and it is set by the computer.

The engine stumble is obviously not a major problem...but it just makes you feel bad when it happens...since this is such a great car and do not expect it from such a quality engine...and I really enjoy the quietness of the car when I just want to unwind.

I am still searching for a cause and solution for the problem. Dealer says its normal. I know from this forum that some owners have it, and some do not...so there must be some adjustment that can be made to eliminate it. I hope someone posts a solution to resolve this problem.

Thanks

 

A stumble is not what I feel. It is just sometimes a rough idle where I can feel a very very slight vibration in the car when it happens. nothing as drastic as a stumble feeling like you metnioned. Also, my engine idles around 700 to 800 rpm mostly. When the vibration hits.. I can see the tach go from 800-700 and then to 800 again.. ever so slightly.

I am comparing this to my Acura TL that I have which has a super smooth engine that you would not know it on when you are at a stop light and the tach is always dead stuck at 800 during idle...

Another reasoning for this slightly rough idle could be due to the fact that the Crossfire engine is a 3 valve design with a single OHC (I don't know if it has a blance shaft to smooth the engine or not). All of my toyota and acuras have been DOHC designs which are by design more balanced than a single over head cam design.. which could explain the slight vibration in the engine...

 

Sometimes I have what feels like a rough idle when stopped. Doesn't happen all the time. It could be that the engine is idling a little low. I think it's supposed to be about 500 rpm when it warms up but I suspect it's down a little and that is what is causing it. In any case the car never stalls or stumbles off the line so I don't worry about it.

 

Believe it or not, when mine is warmed up, it idles at around 300 rpm sometimes. Other times it is around 500rpm. It seems to depend on what the ECU feels like doing at the time.

You know, I know what you are talking about here. I think the reason it doesn't bother me is because I know what real engine stumbling feels like. My Jetta VR6 started stumbling after its O2 sensors failed and the idle was really bad. Compared to that, the Crossfire's little "bit of shaking" is really nothing to me. The idle revs stay dead-on 300-500 rpm and the engine just shakes a little bit for a few seconds.

From my perspective, it would be unfair to call what's happening "engine stumbling". I would describe it more as "idle shake" because it's noiseless. "Engine Stumbling" to me has a very special meaning (engine having problems keeping a steady idle) and usually it sounds terrible.

 

My XFire has 6400 miles on it now and it purrs like a kitten. I have to look at the tach to make sure it's running.

Maybe you idle is set a little low as suggested above. You could try a tank of UIltra 93 at Sunoco if your present filling station isn't up to snuff on their octane ratings. Whatever it is shouldn't be describe as "normal". If that is normal, then mine perfect idle would have to be "abnormal".

Bob M.

 

I've noticed the same thing. I haven't yet put 100 miles on my Crossfire so I'm still learning what "normal" feels like for this car. It's good to know that this slight stumble appears to be common.

 

Thanks everyone for your comments. From the feedback, I guess technically it is not a "stumble" , so I would call it a "rough idle". Thinking about all the comments made, it could be due to a slightly low idle, I know when warm, the car idles at 500 rpm. I will try a test next time I am stopped with the car in drive and feel the rough idle...I will put the car in neutral and see if it still occurs. With the car in neutral, it idles at about 600 rpm. I will also try putting on the AC...since I think that boosts the idle a little also.

I wonder if it occurs on both the limited and srt-6 engines? That info may help to isolate the problem. I will go back through these posts and see if that info is available.

Thanks Everyone

 

I've only noticed it when the car is warm. It does it in neutral and when in gear with the clutch depressed. Although I can feel / hear the idle changing, the needle on the tach doesn't seem to move at all. My car is used with just over 28,000 miles so I was wondering if it needed an injector cleaning or new spark plugs. But, given that cars that are essentially new are having the same issue, it seems to be a common characterisitic of this engine. - Jay

 

When I bought my car it had 250miles on it.. It has always had a rough idle.. At a red light I put one foot on the gas and the other on the break.. As soon as I hit 550rpm or maybe 600 the engine smooths out.. If I don't do that I hear this weird (I'm not sure the best way to explain it) but a whining sound that goes up and down like the engine doesn't have enough power... another problem I see, if I don't keep the RPMs around 550 - 600 the fan kicks on more often and I see my headlights and the interior lights dim a little.. the car drives great once I accelerate.. and there seems to be no loss in power... I also think it could be the gas I use (Moble Premium) 10% ethonal.. but, I'm not sure.. It seems every station here in South FLA.. has 10% of ethonol added to the gas.. I just did an oil & filter change (moble 1 0w40) and put in some Cheveron injector cleaner.. but it doesn't seem to affect the idle..

 

Mine stumbles, idles wierd when stopped... it even makes the typical cluncking noise in the engine. The interior lights dim at stop lights. Sometimes the engine even makes a noise when I turn it off. All of this is normal. It has done this for 4 years since brand new. 50K miles later and everything is the same. Don't worry about it or try to find problems with the car. Everything is normal. If you want a quiet car that idles smooth, get a Lexus, Nissan or Toyota. If you want something with character made by some of the best engineers, keep the car. This is a noisy Mercedes! It takes a million quarts of oil. The parts are expensive! It may sound like it is falling apart when compared to Japanese cars, but it will probably live longer than most of us here. My dad has a 1976 350SL sports car and it sounds the same as my car! It has the same ticking type of noise. Just love the car and enjoy it. This car is a beast and it is just telling you it wants to take off at a stop light!

 

That makes me feel better.. I was thinking of bring it in to the dealer.. (which I feel might turn into a nightmare) I still need to bring it in the passenger seat is not moving up and down.. My jackass friends think buttons and switches are toys.. so I figured he broke it.. anyways.. The only time a ever felt a car shake like this was one with a high duration cam in it!! but, I am happy to see that its normal. Thank you again for all your help, you and this forum has been really helpful to me.. Hopefully I can add some insight in the near future..

 

When I bought may 06 roadster it had a pronounced shake and rumble when idled. It felt like the engine was so big that it had trouble settling down! I have a friend with a coupe and he told me his did not idle rough at all. My Roadster had 2,000 miles on it when I bought. I took it to the dealer and they found a vacuum hose under the engine cover had come lose. After the hose was reconnected the car felt fine. I have no idea if this is what you are experiencing, but I thought I'd pass along what info. I had.
Good Luck

 

Motor Mount?

 

My SRT does this too. It does kind of bother me, it's almost like it has a bigger cam or something. I will however look at those hoses.

I also have a highly modded Buell motorcycle with a huge cam, and you could make milk shakes on the seat when it idles It will actually vibrate accross the garage floor when it is in high idle mode. (my wife loves it ) So I guess compared to that the little shake in the idle of the SRT is nothing.

 

Leon I want to put our cars next to each other and check to see...If I may have a mount busted....500+ pulls at the track may have done something to mine....cause I swear they put a cam in mine!

 

Mine idles a little rough since new. I plan to take a look at the plugs to see how the gaps are. One or two or all could be off, you just never know unless you look. When the car is fully warmed up the idle is 500 rpms. With the air on its 550 or 600, hard to tell for sure on the tachometer. So I would guess its normal even if surprising. My other mercedes (m110 in line 6) is as smooth as silk.

Les