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Discussion Starter #1
anyone had voltage issues? I am having an issue where the voltage in my camaro drops drastically from 14 to 10 volts. it seems to happen most often after I run the RPM's up past 3000 then takes several maybe 10mins for the voltage to jump from 10 to 14 volts (it does not rise slowly it jumps like something reset)

i had a similar issue before where it would not go above 10volts, I replaced the voltage regulator, alternator and plug wires and that seem to fix it. when I was having this problem before the car would barely run, currently I dont seem to be having performance issues.

any ideas
 

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Re: volatage fluxuation

Externally charge the present battery, then try again.
The 14 volt reading tells me the battery needs charging.
Normally, with a warm battery and warm VR, voltage is usually around 13.5 to 13.7 volts after 15-20 minutes of running above 2000 rpm.
Check wire harness from VR to alt. Clean connectors with alcohol.
Ensure both VR chassis is grounded, check bonding strap on the one bolt if using the OE rubber wellnuts, and alt case is grounded, no paint.
Wire brush the two leads and connections on the horn relay buss bar.
If all else fails, get another VR, an electronic one, Wells VR715.
 

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Re: volatage fluxuation

x2 I was thinking it was either dead cell in the battery, or bad ground.
 

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Discussion Starter #4
thanks
i just replaced the VR with the wells VR715 a few months ago. the battery is an Optima red top and the charge is good.

at idle the other day it was 14volts when i drove around and opened it up above 4500 rpm the voltage dropped to 10v and did not return to 14 for almost 10minutes -i hit it pretty hard again and the same thing voltage dropped but now it has not seemed to come back up
 

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Check for a bad diode in the alternator. Best way to test is to disconnect wires to alt. Use an ohm meter, one lead on the batt terminal of the alt and the other lead on alt case. There should be no continuity what so ever. If there is find yourself a new alternator.
 

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I'd replace the alternator belt if it's been on the car for a few years. It's possible it starts slipping and gets hot at higher RPM, and takes several minutes to cool off and resume gripping the alternator pully when you're babying it. Next time it acts up, shut the car off and BRIEFLY touch the alternator pully. If it's REALLY hot, you might just need a new belt.
 

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Discussion Starter #10
ok, charged battery, tested the charging system and everything comes out ok.

test drive 14volts - hard wide open throttle voltage drops to 12volts, cruising some more volts hold a 12 - wide open throttle 6500 rpm volts drop to 10v. cruising some more volts stay at 10v. wide open throttle volts drop to 8v. if you test the charging system it say recharge batter and retest.

I have a MSD6AL is it possible that it draws the battery down that fast on hard acceleration that on short cruises the alternator can not keep up?

i have a 383 stroker that has dual quads and twist off about 485hp at the rear wheels.
 

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Alternator case should be hot to the touch.
Also, if alt is working, you should feel a magnetic pull on a screwdriver held against the rear bearing, perpendicular to the axis. No pull, alt not working.
Install another non-Optima battery and compare results.

So, if you keep engine rpms below, say 3500, alt works fine?
Shoudl work all the time.
No, MSD -6AL should not draw so much current, it pulls down the charging system.
This is why I suggested the heat of the case and screwdriver pull.
If alt is working, it is working to the max capacity.
 
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