Rough start up after changing battery

[Zmann96]

I have a 2013 Expy XLT with 197K miles. I changed the battery and it's starting rough and almost stalls and then it smooths out. I also noticed it's running rich because of a strong gas smell after startup. It was running fine prior to the battery change.

 

[S20Workstation4]

I would start by resetting the PCM. You can follow this video:

- https://www.youtube.com/watch?v=hZAsoqmqhdM

 

[Zmann96]

Thanks for sharing that. I'll do that tomorrow.

 

[Zmann96]

I won't be doing ECU reset today due to weather. I'm hoping it works. I'm 75 and have don't almost all of my repairs and I've never ran into this form changing a battery. Does anyone know why the engine would be having issues starting and having a strong gas smell after changing a battery. It's been 2 weeks now with at least 300 miles and it hasn't relearned by itself ?

 

[bloodhound]

How are your battery terminals? A poor connection can also cause the ECU to do strange things, and since you just had them disconnected for the battery change, could be a possibility. I would think otherwise in 300 miles of driving everything should be good by now. I just did a battery change in my 2014, it caused weird transmission behavior briefly, which is normal while it relearns, but it was back to normal pretty quick.

 

[Zmann96]

Battery terminals are fine, no corrosion at all. It has gotten better at start up, the thing I noticed that I didn't have before is the smell of gas, seems to be running rich. I'll do that procedure that S20workstation4 suggested as soon as the weather clears.

 

[chuck s]

Disconnecting the battery resets the ECU.

I've noted the shop that has changed batteries on several of my cars always connects a little battery powered device to the OBD2 port to keep the ECU powered so it won't forget all the things it's learned when the battery is disconnected (which will reset the ECU).

Yours is probably just relearning everything all over again.

Let us know how the second reset works.

-- Chuck

 

[Zmann96]

will do Chuck. I'll do it while I'm off over the next few days.