Start Stop feature causing rumbling sound Lacrosse 2017
 

Hello Everyone:

Have a 2017 Lacrosse with the new start/stop feature.

After several cycles of starting and stopping, along many lights/stop signs, when the car starts to accelerate after a stop, it may exhibit a rumbling noise upon accelerating. Rumbling is from engine/trans area. It does not happen all the time, only once in maybe 50 start/stops, but it does happen. Took it to dealer, could not reproduce, no trouble codes. Ran VIN, no recalls or service bulletins. Local mechanic can only say it is possibly related to start/stop since rest of car checks out. It's a good local mechanic. Dealer is saying no trouble found.

I appreciate any suggestions/ideas you may have.
thanks!

If you have a pretty good idea of approx when it will do it , can you time it to have the dealership tech take a ride with you .

Hi Hanky:

Thank you for the reply. It's a good suggestion. Could be after so many minutes of driving, or miles, or number of stops. I'll keep an eye to hopefully see a pattern and then get a tech to sit in.

Take care.