Low Battery Voltage After 3500 Stall
08-07-2010, 11:05 PM
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Low Battery Voltage After 3500 Stall I had a 3500 stall put in and the now the battery is not getting recharged when the car is running. Before the install the battery voltage was at 14.1 volts. Now with the car running the battery voltage is 13.1 volts with nothing on and between 13.0 and 12.7 volts with the stereo on. I do not have any after market speakers, amps, or subs. The car always ideled alittle low but it is ideling between 450 and 500 RPM. I wouldent think I would need a tune after putting the stall in. Has anyone had this issue after getting a stall? I have already gotten a tune from frost before I got the stall. do i need to get it retuned to work with this stall? Thanks
08-07-2010, 11:13 PM
#2
Frankly I dont see that to be a problem, those voltages seem fine. Maybe the stall affects the RPMs in a way that results in a bit less voltage. Mine lacks a stall and running with lights on the voltage drops to almost 11.0! I have the repair manuals and they say that the lowest voltage considered normal is 11.1, according to GM specifications.
08-07-2010, 11:35 PM
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11.1 voltage normal? Maybe while the starter is engaged. a lead acid battery begins to sulfate at 12.4 volts and below. 11.9 volts is considered discharged. I cant believe Gm really said 11.1 volts is normal?
08-07-2010, 11:51 PM
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I dont believe it either. The stock alternator is crap, IMO.
08-08-2010, 08:16 AM
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I thought anything below 14 would cause the battery not to charge. If we are running on a 12V system how could 11.1V charge a 12V battery. The alternator has to be pushing a voltage over 12 for it to charge. Would increasing the idle with a tune increase the voltage and current from the alternator?
08-08-2010, 11:13 AM
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rev the motor while keeping the meter on the battery and measure. At 400-500rpm your really not turning the alt fast enough if there is any load on it. Do you have a underdrive pulley? Idle should be minimum like 600 and you should see max voltage at probably 1000 or above.
The faster the alt spins the more amps and voltage it will make, but the voltage regulator will keep the output voltage around 14.4-14.2.
Your stall in no way should effect idle speed or alternator output.
The faster the alt spins the more amps and voltage it will make, but the voltage regulator will keep the output voltage around 14.4-14.2.
Your stall in no way should effect idle speed or alternator output.
08-08-2010, 11:51 AM
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I still have the Stock pulley. I have driven the car with the stall for approx 35 miles and when I do an OBDII emission test the EVAP says its not ready. As of right now I have no SES light. Does this mean that I could have a vaccum leak and that is why it is ideling so low? It takes a bit to get of gas to get the car moving and if I push gas rapidly and then let off while backing up the RPMs dip to around 400 and then back to 500.
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08-08-2010, 11:53 AM
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Also when I am driving above 1000 RPM I am not seeing any difference in the output voltage from the alternator. Granted I am measureing the voltage with my pioneer head unit. There is systems tab on the NAV screen that measures the voltage into the head unit. It seems to be accorate because the battery voltage on the dash is always in the yellow which it never was before.
