Concerning Battery Charge/Alternator
05-25-2016, 02:28 AM
#1
Concerning Battery Charge/Alternator
So, this thread may seem redundant, but I found I have a problem with my car that I'm struggling to solve using previous threads. It's not too hard to fix, but if I can figure this out, I might be able to save some money... and most of these threads about alternators/battery problems tend to regard someone driving and their "Battery" and "BRAKE" warning lights flash on the dash, there car failing to start one morning, or their car just suddenly dying while whipping down the interstate, but mine isn't quite like that.
Alright, short story to describe my problem. WALL OF TEXT.
I had some senseless, wallet-cringing, overly-extensive work done on my Max over the past 2 months. Drove the car home over 500 miles with base electronics. Bare-minimum electronics now being my ECU, headlights, UTEC, and instrument cluster/gauges. No radio, extra fancy lights, or anything. No problems. I don't believe any of this work to be the problem either - but onward.
I get the car home, do my oil change a couple days later, and reassemble my two amps, for my sound system, along with a new large capacitor. Hook the stuff up in my neighbors garage, play some tunes, good to go. Next day fuel leak, so we'll skip a couple days until after I fixed that. So I fixed the fuel leak, start the car, let it warm up and I'm pumped for a joyride. Hop in the car, drive downtown with my sound system booming like I always did, and the car starts running very rough at stops when I reach the city.
Running rough at a stop isn't completely abnormal for this car since I still need to change my spark plugs, and it gets a lot hotter with my new setup, let alone it's about 90 outside, but here it starts idling excessively low. I'm worrying about the car dying, and my system is still up, and by the next stop, when I go to hit the gas, there's no throttle response. I finally get a response, turn the music off, and by the next light, it's running scary low, so I shut it off, and when I try to restart, no response. Car is dead.
So I get some help to push to a parking spot and I try to start the car until it just clicks. Windows barely managed to roll up and it's obvious the battery is dead at this point. After about 10 minutes, help arrives, and I let the car battery charge on a jump for a few minutes while checking everything under the hood. Then I go ahead and start the car, after detaching the sound system and everything is good. I proceed to drive the car home, let it sit and idle for a few minutes, then drive it to a friend's place on the other side of the city. No problems, but I left the sound system unattached.
This is what gets me though... My battery/brake light won't appear while the motor is running and I'm driving. My battery/brake light DO however appear on when the key is put into the ON position. I can check voltages in the trunk and the battery reads about 11.8-12V when car is off after sitting for a few hours or overnight, and when first started, it jumps to about 13.1-13.7V, and after driving and sitting back at idle to check, it tends to rest between 12.4-12.8V, scaling between depending on the load. I know this because I have since reattached my sound system, and have been using it lightly just to have some music and to test levels here. At this point I'm certain that the presence of a 12v load on the system with the volume off has no effect on the battery. I'm pretty certain that the drain from the sound system being used in full effect did help to quickly kill my car when I had this incident, but I have never experienced this before doing the same thing in the past.
Oddly enough, since I jumped the car, it has often times been running a lot smoother at stops and idle, even after a spirited drive in the heat. Smoother meaning that the A/F ratio is in the ideal range, and it's not idling too low. These lights still appear when the key is turned to the ON position, and I know that some lights appear when the car is started just to alert the driver that they still work properly. I also know that these lights are active when the key is in the ON position because if I put the parking brake down, the brake light still appears. The service manual says that these lights will only appear on the dash when the car is started as a test, and implies that there is a problem with the battery/alternator when they show while the car motor is running. I did a little backpedaling to find videos where I start the car in the past, and a video I made several months ago did not have the lights present in the ON position. I found a video I made just last week before I had this problem, and these lights were on when the key was in the ON position. Obviously these lights are indicating a warning, but I find it odd I can't get them to show while the car is running since that seems to be the telltale sign.
Moral of the story is that while I'm assuming I have an alternator problem, or I'm on the slope of it dying, I was just curious to see if anyone has any experience like I had in this situation. I can't really nail it as being one or the other, battery or alternator, since the voltages seem about normal to me, minus the initial motor starting voltage of 13+ then it drops and stays consistently mid-12 average at any amount of load. I've checked under the hood and the harness looks fine, my terminals are prim and proper. There is an electrical buzz that radiates all around the car though, which I've had as long as I can remember, and it does lower with use of electrical devices, such as the window motors, but you can't hear this while driving or inside the car, and it sounds the same even from behind the car. Also, the battery is holding charge. Before I had this shutoff incident with a dead battery, the car was able to start after a couple days sitting, but I will admit, I had been having some longer starts.
If you want to help, read my story and tell me what you think. Regardless, I plan to take the car in on Thursday to my mechanic for him to take a look since an alternator job for me on a side street, with limited tools, in my city is far from ideal right now, especially when even simple jobs take me way longer than they should. I will add that I don't know if the alternator is original - I've owned and maintained this car for 5 years, and my parents did before they sold it to me. The battery I purchased a little less than two years ago. Could be either or both. I'm all ears.
Let me know if I need to clarify on something. I appreciate any help. Thanks!
Alright, short story to describe my problem. WALL OF TEXT.
I had some senseless, wallet-cringing, overly-extensive work done on my Max over the past 2 months. Drove the car home over 500 miles with base electronics. Bare-minimum electronics now being my ECU, headlights, UTEC, and instrument cluster/gauges. No radio, extra fancy lights, or anything. No problems. I don't believe any of this work to be the problem either - but onward.
I get the car home, do my oil change a couple days later, and reassemble my two amps, for my sound system, along with a new large capacitor. Hook the stuff up in my neighbors garage, play some tunes, good to go. Next day fuel leak, so we'll skip a couple days until after I fixed that. So I fixed the fuel leak, start the car, let it warm up and I'm pumped for a joyride. Hop in the car, drive downtown with my sound system booming like I always did, and the car starts running very rough at stops when I reach the city.
Running rough at a stop isn't completely abnormal for this car since I still need to change my spark plugs, and it gets a lot hotter with my new setup, let alone it's about 90 outside, but here it starts idling excessively low. I'm worrying about the car dying, and my system is still up, and by the next stop, when I go to hit the gas, there's no throttle response. I finally get a response, turn the music off, and by the next light, it's running scary low, so I shut it off, and when I try to restart, no response. Car is dead.
So I get some help to push to a parking spot and I try to start the car until it just clicks. Windows barely managed to roll up and it's obvious the battery is dead at this point. After about 10 minutes, help arrives, and I let the car battery charge on a jump for a few minutes while checking everything under the hood. Then I go ahead and start the car, after detaching the sound system and everything is good. I proceed to drive the car home, let it sit and idle for a few minutes, then drive it to a friend's place on the other side of the city. No problems, but I left the sound system unattached.
This is what gets me though... My battery/brake light won't appear while the motor is running and I'm driving. My battery/brake light DO however appear on when the key is put into the ON position. I can check voltages in the trunk and the battery reads about 11.8-12V when car is off after sitting for a few hours or overnight, and when first started, it jumps to about 13.1-13.7V, and after driving and sitting back at idle to check, it tends to rest between 12.4-12.8V, scaling between depending on the load. I know this because I have since reattached my sound system, and have been using it lightly just to have some music and to test levels here. At this point I'm certain that the presence of a 12v load on the system with the volume off has no effect on the battery. I'm pretty certain that the drain from the sound system being used in full effect did help to quickly kill my car when I had this incident, but I have never experienced this before doing the same thing in the past.
Oddly enough, since I jumped the car, it has often times been running a lot smoother at stops and idle, even after a spirited drive in the heat. Smoother meaning that the A/F ratio is in the ideal range, and it's not idling too low. These lights still appear when the key is turned to the ON position, and I know that some lights appear when the car is started just to alert the driver that they still work properly. I also know that these lights are active when the key is in the ON position because if I put the parking brake down, the brake light still appears. The service manual says that these lights will only appear on the dash when the car is started as a test, and implies that there is a problem with the battery/alternator when they show while the car motor is running. I did a little backpedaling to find videos where I start the car in the past, and a video I made several months ago did not have the lights present in the ON position. I found a video I made just last week before I had this problem, and these lights were on when the key was in the ON position. Obviously these lights are indicating a warning, but I find it odd I can't get them to show while the car is running since that seems to be the telltale sign.
Moral of the story is that while I'm assuming I have an alternator problem, or I'm on the slope of it dying, I was just curious to see if anyone has any experience like I had in this situation. I can't really nail it as being one or the other, battery or alternator, since the voltages seem about normal to me, minus the initial motor starting voltage of 13+ then it drops and stays consistently mid-12 average at any amount of load. I've checked under the hood and the harness looks fine, my terminals are prim and proper. There is an electrical buzz that radiates all around the car though, which I've had as long as I can remember, and it does lower with use of electrical devices, such as the window motors, but you can't hear this while driving or inside the car, and it sounds the same even from behind the car. Also, the battery is holding charge. Before I had this shutoff incident with a dead battery, the car was able to start after a couple days sitting, but I will admit, I had been having some longer starts.
If you want to help, read my story and tell me what you think. Regardless, I plan to take the car in on Thursday to my mechanic for him to take a look since an alternator job for me on a side street, with limited tools, in my city is far from ideal right now, especially when even simple jobs take me way longer than they should. I will add that I don't know if the alternator is original - I've owned and maintained this car for 5 years, and my parents did before they sold it to me. The battery I purchased a little less than two years ago. Could be either or both. I'm all ears.
Let me know if I need to clarify on something. I appreciate any help. Thanks!
Last edited by Cotozic; 05-25-2016 at 02:31 AM.
05-25-2016, 04:03 AM
#2
Member
Join Date: May 2004
Posts: 279
You should really condense the "story", but the voltage of 11.8/12v, after sitting, is entirely too low, and when running, 13.8/14+ should be seen. Both the battery and alternator should be tested and I would also check for any parasitic draw when car is off.
05-25-2016, 09:06 AM
#3
It sounds like alty puts out enough V to keep the cel off, but it must failing hard on amperage (you'd think that would cause a big V drop, though, especially with subs).
And then it looks like bad batt/parasitic drain, too, as the battery should always read over 12v.
Last edited by Child_uv_KoRn; 05-25-2016 at 09:12 AM.
05-25-2016, 07:39 PM
#4
There isn't any noticeable drain. The car has consistently been 12v after sitting and turning the key to ON. I haven't checked the CEL codes yet since I no longer have my OBD2 reader and I'm already married to the light. Also, I'm certain that the voltage does increase with RPM, I just currently can't check it while in motion. I am familiar with voltage changes with driving since I used to monitor it all the time, but just can't so easily at the moment. Each startup for the past few days has raised to voltage to 13.7 oddly enough. Anything under 13 while on is scary though. I know for sure that right now, it seems to keep up with medium+ RPMs with high amperage - but that's just for the mean time. Definitely can't handle the power at idle.
Tomorrow it'll all get worked out though. I'm fairly certain it is the alternator just being on the verge of failure. Not really interested in letting it get worse.
Thanks for your opinions. I think the long wall of text kind of writings tend to happen when I decide to stay up til 5AM and make a post.
Tomorrow it'll all get worked out though. I'm fairly certain it is the alternator just being on the verge of failure. Not really interested in letting it get worse.
Thanks for your opinions. I think the long wall of text kind of writings tend to happen when I decide to stay up til 5AM and make a post.
Last edited by Cotozic; 05-25-2016 at 07:55 PM.
05-27-2016, 07:27 PM
#5
I figured this one out today. Alternator checked out fine by mechanic. Battery was a concern.
The battery is about 2 years old, gold top battery that was pretty decent but took a lot of love. I'm assuming because my car was idling rough at stops because of the heat, and with the amps using a lot of power, the alternator was not able to keep up since the RPMS were sinking very low, as well as the battery already was very reliant on a constant charge.
Went ahead and replaced it with a Yellow Optima battery. Tested it out - watched the voltages. No problem. Stays up in the upper 3.0s when on, and doesn't ever fall below 12.6 even when off. I can sit and play music at idle, no problem.
Maybe this thread can help someone else. Thanks guys!
The battery is about 2 years old, gold top battery that was pretty decent but took a lot of love. I'm assuming because my car was idling rough at stops because of the heat, and with the amps using a lot of power, the alternator was not able to keep up since the RPMS were sinking very low, as well as the battery already was very reliant on a constant charge.
Went ahead and replaced it with a Yellow Optima battery. Tested it out - watched the voltages. No problem. Stays up in the upper 3.0s when on, and doesn't ever fall below 12.6 even when off. I can sit and play music at idle, no problem.
Maybe this thread can help someone else. Thanks guys!
05-29-2016, 07:29 PM
#7
Lowest I've seen with the new battery was 12.2V, stopped, car on, hot idling rough (going to adjust the tune for the rough idle when hot), and amps blasting. Usually sits at 12.4/12.6 when off with medium electronic usage. This new battery is deep cycle and has a lot of life when not charging, so that's a buffer. Usually sits over 13.6V when the car is on and at light load.