Hello,
I recently had my water pump changed. Upon leaving the shop, the 'Service Engine Soon' light comes on. Turns out there's also a faulty cam sensor. Had the shop replace that part too. Car was driving good for 2-3 days. This morning, once I got above 55-60 MPH, the 'Service Engine Soon' light started flashing. I didn't notice anything out of the ordinary, car seemed to run normal. The light went away after about 30 seconds. After stopping, I turned the car off and back on. It had to crank a little harder to start but it did. Drove it 45 miles to work, getting up to almost 100 MPH at one point. No lights or issues. Anyone else ever had anything like this happen? I'm worried about a potentially serious issue because of the flashing light but am not sure why it would go away after 30 seconds.

2013 G37S 6 MT, 81k miles.

 

See if there any codes. Any autopart store will do it for free (usually)

 

Unfortunately I got a solid 'Service Engine Soon' light not long after leaving work. Car is back in the shop and I haven't gotten any updates yet.