Lurching + Battery light on

Hi, I have a 318 SE E46, recently I had a new exhaust / cat fitted and ever since I have a problem where a few times a day while driving the battery light comes on and the car jumps forward. This only lasts a split second, the light goes off and the car continues as normal. Happening daily. The garage that fitted the exhaust put it on their diagnostic computer and it isnt showing any faults, I took it to a second garage who ran a test and also couldnt find any fault codes. Any ideas ?

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: Troubleshooting Electrical Problems on Your BMW

[Wayne 962]

Very odd. I have very little clue here. I would remove the battery and have it tested. Also check to make sure all battery grounds are tested and connected. I'll copy this question to the forums, perhaps someone there might have some ideas?

- Wayne