Voltage drops

Shadow222

New Member
Messages
2
Hi Guys,
Anyone had any experience with voltage drop issues while driving? On start up car voltage is somewhere between 13.7-14.2 and will continue to hover around that, but then suddenly voltage will drop and struggle to get back up, it can drop to as low as 11.8/11.6v. Battery and alternator was changed in Jan this year and load test done show no faults with it.

Only reason I noticed this was because the battery light would come on for a second during vtec and then the other night it started flashing again randomly during normal driving.

Anyone got any experience with this?

Thanks

Sam
 

RaspyNoise

Advanced Member
Messages
428
Easy…

At high speed/revs you are running off your battery at that point! I had the same problem with my car on track my old turbo ep3! You need a higher amperage alt. Add up all the electoronis (amperage dram) you have in the car and see if it matches or exceeds the alt amperage! 140 amp ftw!

You battery is the issue even if it’s new it may be a cheap brand possibly?

All you need to do is get a heavy duty full size battery that is a good brand like Bosch, Yuasa etc and all will be good
 

RaspyNoise

Advanced Member
Messages
428
Let me get back to the drawing board.

A battery cannot be simply tested via voltage it needs a load test and new batteries can fail.

Also a new alternator could also fail it may just be bad luck Even though it is new!

It could be a slipping fan auxiliary belt, or similar issues ... yes, a slipping belt could cause the alternator to not charge, which would turn the light on, but it would also cause a voltage drop.
 
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