A flashing CEL is the car telling you to stop immediately. Push the Onstar button and ask them to tell you what codes the car has... But given what you've just said, take it to the dealer ASAP. I haven't heard of it before - off the top of my head the jerking sounds like a jammed or slipping clutch, but no matter what it turns out to be, this is what warranties are for.

 

A flashing CEL is the car telling you to stop immediately.

A flashing CEL (MIL) is actually an OBD2 requirement for a detected engine misfire. Since it only flashes while the misfire is actually present, it might hopefully prompt the operator to "back off" reducing load until the lamp ceases to flash.(depending on the root cause of course)
On the Volt this regulated behavior creates a bit of an odd situation as of course the engine load is more a reflection of existing electrical demand as opposed to merely driver input. So there may be little the operator can do to alleviate the conditions creating the misfire. (other than what you suggest- stop the car!)

Sounds like the misfire DTCs for cyls 1 & 2 were set and rocket's dealer is determining the root cause.
By water I presume they mean in the fuel? on the secondary ignition system? (coils, plugs, plug-wires etc.)
Barring something like a head gasket leak there's really no opportunity for water to get "into the cylinders" so there may have been a communication break-down here.
Let us know what they find
WOT

 

Always call OnStar the instant you get a CEL. Then follow their recommendations. That way you can minimise damage to your car.

 

My problem is the flashing CEL went away. It was only on for a few minutes. The car then continues to jerk without a CEL. The problem is only there while the engine is running. It's going to the dealer this morning. I hope they can fine the problem quick. I need the car for some long road trips starting on Wednesday.

 

@ rocket,

Keep us updated on your Volt when it goes to the dealer today. We're hoping they can diagnose and service your Volt quickly as well. Give us a call if we can be of any assistance to you.

 

Didn't hear back today... still waiting. I'm thinking they are trying to figure it out.

 

The dealer says they have nailed the problem down to an engine misfire on cylinders #1 or #2.
They are still working on it... Hope we can find out what is causing the problem.

 

@ rocket,

That is good to hear that they found the problem. Did they put you in a loaner vehicle while they work on it?

 

They did put me in a Chevy Cruze but its a very weird problem. It appears water has also got in the cylinders causing the misfire. They are working with GM and have a few TAC cases open so see if anyone has seen it before trying to get to the root cause. Also it appears my heat valve was stuck open before the problem happened because I was getting warm air in Fan Only mode while the ICE was on.

 

Also it appears my heat valve was stuck open before the problem happened because I was getting warm air in Fan Only mode while the ICE was on.

Getting heat from the gas engine in Fan Only mode is normal, assuming your cabin temperature setting is set to be higher than the current temperature. Were you getting heat regardless of the cabin temperature setting?

 

Thanks *** for the response. Dealer and GM or pointing to a bad coil that's shorting out the plugs. They are going to try replacing and report back tomorrow. Hope it's that simple of an issue.

 

Did replacing the coil fix the problem?

This also happened to my Volt. OnStar only confirmed what I already knew (i.e., misfire). I popped off the air box, and there was no evidence of any obvious problem (i.e., nothing disconnected or shorting, and no water in the spark plug wells.). Then I took it to the dealer, and all they did was reset the code and told me that it wasn't happening any more. I suspect that they were test driving it on battery power (so of course the engine doesn't misfire!). I have found that very few people at the dealership even understand the basics of how a Volt works.

Now it is happening again. I do not want to play this 'back and forth' game with the dealership. I think the invoice had the particular codes that the technicians read out. Maybe I can find a secret decoder ring somewhere on the web ...

 

I was getting heat. I'll double check...

So the thought is right now is that a bottom spray car wash caused water to collect and shorted out coils on cylinder one and two. They said my car is fixed and I'll be picking it up tomorrow.

 

how much did this end up costing you if you don’t mind me asking? I believe I am having exact same issue

 

Our 2012 is having the very same issue. I had OnStar run a diagnostic test. I do not have the error code, but the rep told my wife that the engine is misfiring and we are to bring the car in immediately. My wife was told by the rep that the car would behave sluggishly - also shake and possibly stall - and we are to avoid, among other things, pressing the accelerator or going up hills. In other words, do not drive the car.

I have scheduled to bring the vehicle into the dealership Tuesday morning. The dealer's service department seems to think this problem is nothing major and was quite breezy about the issue.

My biggest beef is that I do not get a loaner car. What the $%#?

 

They should be providing a rental as its part of your warranty.

 

* Diagnostic Trouble Codes (as retrieved by the GM dealer technician):

P0101 = "Mass/Volume Air Flow Circ Range/Perf"
P0300 = "Random/Multiple Cylinder Misfire Detected"

 

In case this ever happens to anyone else, I'll share the resolution. After the first trip to the dealer, I tried adding some Iso-Heet to the fuel tank (in case there was water). After about an hour of cumulative engine run time, I noticed the following:

* The misfire didn't occur until the engine got warm (10 minutes or so), then it gradually worsened.
* The Iso-Heet did not solve the problem.
* It sure would have been nice to have had Hold Mode so that I could have driven around testing the engine, but could have used the battery to get home if the engine completely quit.

So I took it back to the dealer. This time, they let it run long enough to duplicate the problem. They then discovered water and rust inside the spark plug wells (It is a "Hemi" head, so it can trap water down there.), so they replaced the coil module and the spark plugs. Both the dealer and I have since confirmed that the problem is now fixed.

Now I wonder how the water got in there, and why it didn't boil off from the engine heat. Was it spraying/splashing from underneath due to wet roads and puddles? Did it somehow get in there while I was washing the car under the hood (but didn't cause problems for months)? Given that I don't see complaints from other Volt owners (who live in soggy climates) here, I can probably conclude that it is *not* a design problem, and thus discount road spray as a cause. So I will have to be more careful when washing the car not to spray under the air box.

 

engine misfire

I am in the middle of having this problem resolved. It started out with the misfire and the flashing engine light. The misfire would stop and the engine would smooth out. First the coil was replaced. The next time it happened all four fuel injectors were replaced. This time the head is going to be replaced. My service dept. tells me that this is a problem being seen in various parts of the country.
I've been given a new 2014 Equinox to drive while the part arrives and repairs are made.
The first year I owned my Volt I ran on electric almost all the time. Now I have a 55 mile one-way commute so the engine comes on every day.
My dealership has my confidence that this will be resolved.

 

I am in the middle of having this problem resolved. It started out with the misfire and the flashing engine light. The misfire would stop and the engine would smooth out. First the coil was replaced. The next time it happened all four fuel injectors were replaced. This time the head is going to be replaced. My service dept. tells me that this is a problem being seen in various parts of the country.
I've been given a new 2014 Equinox to drive while the part arrives and repairs are made.
The first year I owned my Volt I ran on electric almost all the time. Now I have a 55 mile one-way commute so the engine comes on every day.
My dealership has my confidence that this will be resolved.

Good Morning R16bacon,

Could you please PM me the last 8 of your VIN, I would like to look into this for you.

-Ian Chevrolet EV Customer Service

 

With this issue happening to more Volts, can anything be done proactively? If I run the engine long enough, will it evaporate the water out of the plug pockets? I only run the engine for hour or less once or twice a month. Will running the engine more often, like cold mornings, help keep the engine dry? Maybe leaving the 'engine heat assist' at 'cold temp' instead of 'very cold temp' might help?

 

I'm having a similar issue with a 2013 Chevy Volt (leased it two months ago). It runs great on battery, but on gas it sputters, shakes, and occasionally dies when accelerating from a stop. I took it in last week, the dealership updated the software but said they couldn't find anything wrong with it. I drove it home yesterday (on gas) and it ran fine. This morning it's back to the same issues. I agree with BobG and ronmaf: the dealership's service group doesn't seemed to be adequately trained on the Volt. They're really communicative and doing everything they can to help, but the guy straight up told me there are a million things that could be wrong and until the computer tells him which one it is, he can't do too much.

 

Having a similar problem as all others here. 2012 Volt started misfiring with flashing CEL. Went to dealership but they were unable to duplicate the problem. Get the car back, same thing happens again. Take car to dealership, they cannot duplicate the problem. They have a code that says misfire, but no direct idea what is causing the misfire, that's all they know. Car has been at dealership for a week and they still cannot locate the problem. I have read many other posts in regards to this problem and seems no one really knows what it is....any help ?

 

Optionally, get the diagnostic codes from OnStar. Definitely call the Volt Advisors at (877)486-5846 with your VIN handy. They may point you at a different dealership; they know which are Volt certified.