Voltage drop at stops!

jchammond · 02-12-2019, 05:41 AM

Don’t forget to check connections at starter as well; a little bit tougher to get to & ensure you have a good ground. Extra ground leads don’t hurt & for the record...12.60 is a fully charged battery...14.5volts while running would be about the max voltage you’d want it set to. AGM batteries prefer closer to 14.0
Ck idle rpm; as TB’s or Maf’s may need cleaning & don’t forget about a quality serpentine belt...good insurance to replace every 50-60k

Rogue Z · 03-27-2019, 02:56 PM

I had Nissan "check the wires and connection". The serpentine belt looks good was thinking of replacing it soon. I haven't driven the car for 2 weeks and now the car is runnimg closer to 15v, with a drop to 13 at stops.

bunk · 03-27-2019, 05:45 PM

Try this... Take your voltage meter, set it to A/C and measure it across the battery while its idling. It should not give you a reading (take it through all of the scale settings). If you get a reading, then its a faulty alternator

Z34Life · 03-28-2019, 10:57 PM

i have the same problem at the moment as well. If I start the car, it idles at 14V. I can leave the car idling for 15 20 minutes and the voltage wont change. However if or when i start driving the voltage will fall to 12.6V as well and i could drive over a bump or something and the voltage will move around.

Possibility:

Im investigating the thought that it could be a slipping Serpentine belt due to a loose tensioner. il come back to you on this.

Z34Life · 03-30-2019, 04:05 AM

Quote:

Originally Posted by Z34Life

i have the same problem at the moment as well. If I start the car, it idles at 14V. I can leave the car idling for 15 20 minutes and the voltage wont change. However if or when i start driving the voltage will fall to 12.6V as well and i could drive over a bump or something and the voltage will move around.

Possibility:

Im investigating the thought that it could be a slipping Serpentine belt due to a loose tensioner. il come back to you on this.

Looks like it was a battery issue for me. One of the cells was playing up and thus the intermittent nature of it. my cranking output was also half now due to this issue. Luckily it was under the battery manufacturer warranty.

02-12-2019, 05:41 AM	#16 (permalink)
jchammond A True Z Fanatic Join Date: Nov 2014 Location: South Carolina Age: 58 Posts: 15,204 Drives: 13’ 370Z TS 7A/T Rep Power: 2684395	Don’t forget to check connections at starter as well; a little bit tougher to get to & ensure you have a good ground. Extra ground leads don’t hurt & for the record...12.60 is a fully charged battery...14.5volts while running would be about the max voltage you’d want it set to. AGM batteries prefer closer to 14.0 Ck idle rpm; as TB’s or Maf’s may need cleaning & don’t forget about a quality serpentine belt...good insurance to replace every 50-60k SouthArk370Z likes this. __________________ MazWorx built long block \| FI-TT-100 Stage 2.75 \| IPT built 7A/T http://www.the370z.com/members-370z-...s-musings.html

03-27-2019, 02:56 PM	#17 (permalink)
Rogue Z Track Member Join Date: May 2009 Location: Los Angeles Posts: 559 Drives: 2009 Silver MT 370Z Rep Power: 18	I had Nissan "check the wires and connection". The serpentine belt looks good was thinking of replacing it soon. I haven't driven the car for 2 weeks and now the car is runnimg closer to 15v, with a drop to 13 at stops. __________________

03-27-2019, 05:45 PM	#18 (permalink)
bunk A True Z Fanatic Join Date: Mar 2018 Location: Southern California Posts: 4,077 Drives: 2010 370z Roadster Rep Power: 2684369	Try this... Take your voltage meter, set it to A/C and measure it across the battery while its idling. It should not give you a reading (take it through all of the scale settings). If you get a reading, then its a faulty alternator __________________ -Drop in K&N Filter -Invidia Gemini CBE -Z1 Oil Cooler -Swift Springs - EcuTek -Forgestar F14 -SPL Camber Links -Akebono BBK Upgrade -Z1 Premium SS Lines -SPL Diff Bushings -SPL FUCAs - BellRaceworks Diff Brace

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Front bump stops pics?	Ni55anPat	Brakes & Suspension	0	10-17-2012 10:38 PM
tach works, then stops on my 96 300zx tt	ernie	Other Vehicles	8	08-07-2012 02:47 PM
The Red Sox pulling all the stops!!!	PapoZalsa	Sports	0	12-09-2010 07:06 PM
1,400 miles and now odometer stops working?	SlowNCurious	Nissan 370Z Warranty / Scheduled Maintenance / Servicing / Repairs	8	11-27-2010 01:19 PM
Lexus LFA Stops by Forged Performance.	Tray@Forged	Other Vehicles	29	09-23-2010 11:31 PM

03-28-2019, 10:57 PM	#19 (permalink)
Z34Life Base Member Join Date: Jun 2014 Location: Sydney Australia Posts: 39 Drives: 12 Nissan 370Z M6 Rep Power: 11	i have the same problem at the moment as well. If I start the car, it idles at 14V. I can leave the car idling for 15 20 minutes and the voltage wont change. However if or when i start driving the voltage will fall to 12.6V as well and i could drive over a bump or something and the voltage will move around. Possibility: Im investigating the thought that it could be a slipping Serpentine belt due to a loose tensioner. il come back to you on this.