2016 Nissan versa (4-speed Automatic). Rpm needle goes up and down slightly when I turn on hazard lights when the car is idle. Also if the car is in D, the rpm gets down to 500 even if the hazard lights are off and there is a slight vibration. It's in normal 750 when it's in N or P.
I changed the spark plugs, ignition coils, motor and trans mounts (all oem parts.)
The shop I took it to to change the motor mounts told me that the ground wiring is weak, putting a load on the alternator to charge the battery (both are fine according to them.) They cleaned the wiring harnesses but to no avail.
What could be the issue?
Well it's obviously some type of electrical problem. I would load test the battery and the alternator myself, as I don't trust anybody and I've seen people say they were good when they were actually bad. Find a mechanic who's got a really good electrical testing system. If you're anywhere near Clarksville, Tennessee, I check them out free during the weekdays. And of course it could be a wiring failure somewhere or a wire is corroded, connectors, bad, etc
