Code UO1000, randomly car shuts off

Hi, I'm Dan.

If the car stalls out it could any number of things. When the car is not running is when you would have to check for the cause. I've attached a guide to help. We need to try to narrow down the issue to fuel, spark, or electrical.
That U1000 code is a communication code, meaning that there is a module on the network that is not talking to the other modules. Which module was the code stored in? The PCM?


https://www.2carpros.com/articles/engine-stalls

It says PCM/ECM "A" lost communication U01000.

I have seen this a number of times. This code is set basically when another module is expecting some information from the PCM but it never gets it due to it shutting off.

There are a couple things that could cause this. So when you replaced the plugs, what brand plug did you use? If you used a split fire of something else then that will cause this.

However, if you used a Champion plug then more then likely you have a PCM or crank sensor issue.

What happens is when these start to fail they are susceptible to excessive electrical interference. So if it were me, I would make sure the plugs are Champion and then replace the Crank sensor before you replace the PCM.

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

I am attaching the info below on this code. Please run through this info and let us know what you find with this. Thanks

I will give it a shot tomorrow. Thank you

Sounds great. Thanks for the update. We will wait to hear back from you. Thanks

Hello , replaced crankshaft sensor and it doesn't seem to have "fixed" my problem. Still cut off. any help would be greatly appreciated.

Also , the plugs are Champion Platinum. That's what they said was stock.

Is this code always active or does it go stored and you can clear it until it cuts off again?

If so, does your scan tool say what module is actually setting this code? Basically we are trying to work through the steps that I attached before so we are going to have to find this info or we may have to just replace the PCM without confirming it.

Lastly we need to confirm this is the only code you are getting when this stalls. So it is important to know if this code was just there one time or it has been cleared and comes back each time it stalls.

Thanks

Hello, it has only appeared twice. Both times I was able to clear it. As far as module is concerned I believe it is "A" does that sound right? Yes, this is the only code it has thrown.

Note: I replaced the crankshaft sensor and drove it maybe four miles and it stalled. Today I drove it about fifty miles and it ran fine. The Idle is kind of rough when it comes to a stop but is not horrible.

Okay. That code is telling you that some other module like the transmission controller or ABS or drivetrain control module (4WD) was not able to communicate with the PCM when it needed to. So it is not going to name it in the title of the code. It is going to be in the scan tool that says something like ABS - U0100- PCM/ECM "A" lost communication. This means the ABS is what lost communication with the PCM. However, your tool may not give this level of detail at which point we should ignore it.

If this code is active when this happens then the module that set the code against the PCM would be the issue. However, if it is stored and it not there each time it stalls then it is not related or at least not causing the stall.

That means we have a rough idle and stall with no codes. That means we most likely have a based engine issue. So does your scan tool monitor the o2 sensor data?

If so, what does it read while you are driving and when it stalls?

I am concerned with either the short term fuel trims or o2 sensor voltages. They are not the easiest to watch when driving so either have someone else drive or just set your phone up to record about 15-20 second video when it is idling rough and then what it does if you can catch it stalling.

However, I think we need to chase down a vacuum leak and just eliminate that as that would be the likely cause of something like this.

Here is a guide that will help find it:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Good afternoon, well here is the latest. I drove the car without any problems for the last couple of days. Quite literally 100.5 miles and Bing check engine light.

Pulled the code and it is P2006 , fuel level sensor "B" performance.

To bring you up to speed. Car would stall all the time. Basically as if you turned it off. Here is the repair list so far:

Fuel tank
Fuel pump
Fuel transfer pump
Spark plugs
Crankshaft position sensor
Battery

I think that is it.

Any help would be greatly appreciated.

Did the car stall when this happened? If not, then we need to start a new post as this is most likely a different issue. I understand that the check engine light came on but there are 1,000 reasons this could happen.

Basically we need to keep each post to one issue and this was the U code and stalling so if we have a different code and no stalling then we need to start a new issue.

https://www.2carpros.com/questions/new

Sorry for any inconvenience but others will not find the solution to this issue if it is under this post.

Thanks

Sorry as this is the first time I ever did a post thing.

No apologies needed. We are here to help but our goal is to not only help you but make it so that others can find your solution so they can do what you did if they have the same issue. So that is the only reason we need to do that.

Thanks for using 2CarPros.

Hello , I have the car listed above 300c. I have been working with your boards and I think I am heading in the right direction? Car will randomly stall for no reason. So far I have replaced: fuel tank , both fuel pumps , spark plugs (stock Champion ) cleaned all electrical connections, crankshaft sensor and battery. It ran for a week and now it has the following codes:
U0100 , ECM/PCM "A"
P0700 Transmission MIL Request

Any help would be greatly appreciated