This morning it was about 40F outside, not particularly cold. When I went to start my 2012 MCS, it sputtered for a few seconds and then died. After waiting a few moments I tried again, this time blipping the throttle when the engine came on. It stayed on after that. Afterwards I check the owners manual for any specific info on starting the car in cold weather, but all it said was "Don't press the throttle as you push the start/stop button" and "don't let the car warm up at a standstill." Should I be worried? For reference, I just had my car serviced for a bad thermostat. It's not doing the same things as before (the fan is not coming on/staying on when it shouldn't). https://www.northamericanmotoring.co...o-service.html

 

Was going to say the thermostat sensor but that's been fixed. I guess it's possibly you could have another bad one.
How many miles on the car?
Only other thing I can think of is the HPFP but since I've never had an issue with mine I'm not sure what the symptoms are.
You do use premium fuel, correct?
May have even gotten some bad gas. Maybe try another gas station.
Just some thoughts for you.

Someone will ring in and give some help.

 

My 2011 did this and it was tracked back to some sort of computer flash that needed to be done.

 

It's a 2012 MCS - about 6500 miles. I always use premium. The car was parked on a slight incline and had only 1/4 tank of gas remaining. Maybe it was a fuel delivery issue? Still, I'll be pretty pissed if that would cause this.

 

That's interesting, mine(2011 MCS, 26K) is in the shop right now as week speak as of today because of the sputter and die on cold start. That happened to me two days ago. But it has been sputtering to start every morning for the past five days. So I will let you know as soon as I hear from the dealership.

Good luck on whatever you may do.

 

I think I have this cold start issue as well. It has not stalled because I give it some gas but I think it would die out. Car has 600 Miles on it.

 

DANG DUDE!!! 600 miles?!?! A 2012 or 2011?!

 

2012!!!

I hope I really didn't make a mistake buying this car.

 

You didn't make a mistake, but the car is very unique, remember that. But take it to your dealer asap if I were you.

 

Ok, this is weird...2012s with a start problem just now showing up and just as mine has had that problem (2012 w/~5500 miles). Actually, it happened 2 days ago. It too is in the shop now. What happened was that I ran it for a while. Came back home and went to restart it after about 2-3 hrs it would just crank. It still had 3 bars of gas (stupid gage), but I put about a gallon of gas in and it started. Don't know if that did it but either letting it sit about 20 min, adding gas or both seemed to help. But it has started funny since then. It will sputter a bit before it really catches on. The SA said that now that warmer weather is in, he is seeing some bad temperature sensors and it tells the computer that the engine has overheated. Another interesting point is that the engine temperature on my ScanGage will jump around once it is warmed up. It usually runs right at 225. Yesterday, it was jumping between 217 and 227. Today it went up to 231.

 

I filled up with premium from a different station than usual today. I'll see how it goes in the morning. Otherwise I'll be scheduling a service...if they have loaners this time -.-

 

Mine started up fine today.

 

Mine also, but it was significantly warmer today 50/60F.

 

Well the dealer took my car in after I took it in yesterday after the sputter and die on cold start in the mornings. I had a good battery but it needed to be recharged, which it obviously does it on its own while driving the car. They did it anyway at the dealership and they said it didn't do it any other time while it was there. So they said I can pick it up today but I chose to leave it there for one more night so they can see if it does it again tomorrow morning. Good luck to the rest of you that have this problem, hopefully it isn't as bad as some think.

 

I have this problem as well. It only happens when its cold, like after 10 seconds or so after starting the car as the rpm's drop it will almost stall, but after driving a tiny bit it idles fine.

My theory is that maybe we have thicker oil then normal or what we should be running to help the break-in (or just crummy oil to begin with) that when the oils cold it will drag down the rpm's slightly.

Mine is also a '12 MCS with only 2,300 miles on it and it's be doing this right after the first month in January. I might just do a simple oil change myself when I get to 3,000 miles to see if that helps, but if it doesn't then off to the dealer I go.

 

I doubt that it's the oil causing your issue.
I'm not sure what it could be. If it persists,
I'd surely bring it in and have them check it out.

 

Mine sputters and dies about once a week

 

Well scratch that, I guess I don't have my car right now:-/. The dealer called me earlier this morning saying that it did sputter and almost died. So the adviser told me it is probably the termastat...and said it was probably a bad one they put on when I brought it in a few weeks ago. I am kinda ticked off, I just wonder how much more I can take with this "Unique car":-D. So I'll keep everyone updated til tomorrow when they tell me what exactly is the problem, again.

 

Aw bummer, at least a thermastat isn't that bad. Thanks for the update, I'll make note of it when I take mine in.

 

2011 s, 16k on the clock...on my third thermostate sensor

 

I am so annoyed. I understand that seriously sucks for you. I feel bad but I don't understand why they didn't fix this problem if they knew it was this bad. I am on my second one still at 26K on my 11' MCS. But they said it wasn't the thermastat so they said they obviously charged my battery even though it was still good(Good=Recharge). The adviser told me that it was "probably bad gas"...really? I always put in BP,Speedway, and Shell. So I was kinda confused. He said stick to one brand and I guess now I'll stick on Shell. Good luck to you guys whatever happens to your cars.

 

Is there an after market replacement...or are people stuck with this piece of crap OEM part?

 

Just had mine thermastat fixed. SA seemed to know what it was just from my discription over the phone. They were able to test it and found it to be bad. They worked me in the day I was supposed to take it on vacation. Car seems to run better now than when it was new.

One of the best things that anyone can do is invest in a ScanGage and watch the temperature reading. That's how I found my problem. The engine temperature was bouncing all over the place. With that said, now that it has been replaced, the engine temp is 5 - 10 deg cooler than when the car was new. Anyone else with a temp gage see that?

 

my 2009 MCS does the same thing but i have to try like 3-4 times before it starts and runs fine. i’ve tried gas treatment and oil changes and nothing works

 

I just started having this issue last night. It's taken 4 tries to start from cold the last 2 times. I've been driving only short trips to and from work for many months, could this have caused carbon buildup or something? Also, I've been using only regular gas since prices started to go up 18 months ago with no reduction in mileage, but maybe the lower octane has caused carbon related issues?