4.6is stuttering
 

Hello guys. I brought my 4.6 to have a water pump replaced air recharged and determine why the ses is on. Little over a month there I just picked it up. Every thing seemed fine air cold driving smooth no lights on. Stopped for gas filled it up. On the way home it started to stutter and was shaking at idle. The ses flashed twice and went off the whole ride home stuttered a bit no ses for the remainder of the drive home.
While it was there the right cylinders had a bit of carbon build up and that was causing to throw a code. They tried sea foam not to start to take the engine apart Code went away no ses then passed inspection.
So for the strange and random ruff idle could it be from it sitting for over a month with out it being really driven as well as some seafoam still not burnt off? Possible a tank of bad gas?

Thanks guys!

Cause of the ses could be many things. You're on the right track seeing if its bad gas. If it still isn't right check/ change the plugs and coils.

Plugs/coilpacks good place to start, fresh gas, check ccv's can cause same issue.

Add the fuel filter to the above list of items to replace if they have NOT been done in the last 25,000 miles. Add a can of injector cleaner to the fuel tank. Techron is one of the best. You can buy it as a BMW labeled product or at your local COSTCO or parts store

LINK for more info: Products

Since you had the SES light on, you should have a logged fault code(s). Get the X scan and provide us with code(s) that came up. Anything right now is just a WAG (AKA wild ass guess).

^^:iagree: you can throw some Techron in the meantime but if your indy was supposed to fix the SES light and theres still an issue I would take it back. Or find an indy who is better at troubleshooting and doesnt take a month to fix something lol

If the SES light was flashing, it means the problem could potentially damage the catalytic converter(s). The problem is usually a misfire caused by a faulty ignition coil.

Of course, it's impossible to diagnose over the Internet. But based on your description and my personal experience, that's the first thing that popped into my head. In other words, a faulty coil would cause those symptoms - and can be intermittent. So it's where I would start troubleshooting if it were my car.

Sometimes these problems can clear up if you shut off the car and restart. This may buy you some time, but there is most likely a new coils or coils in your near future.