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7

The "9/16" marker (at Walmart, at least) is the nominal date of manufacture - the actual date may be a few weeks earlier. It's used for warranty replacements. Walmart batteries are often on a 3+2 warranty - if it fails within the first three years, you get a completely free replacement battery. If it fails in years 4 or 5, you get a pro-rated discount on a ...


7

No, these are not sell-by dates or expiration dates. If batteries expired within a couple of months of manufacture, they'd be useless for their intended purpose. Getting a battery that's been manufactured in the same month you bought it would be unlikely. Batteries are big and heavy, and in many cases are manufactured overseas. A month or two one way or the ...


6

This is a bad idea. There's a very good reason why ECU's default to running on the rich side when they are unable to get a valid reading from the O2 sensor and that is because running an engine too lean can cause quite substantial amounts of damage. If you were able to (somehow) simulate the fluctuating readings within the "acceptable" range the ECU ...


4

The work that a battery can do is measured in watt-hours. You observe that a high or low voltage across the terminals somewhats reflect the state of charge of the battery. That is true, but it's not a reliable measurement of anything else. Batteries of different ages, or with different chemistries and internal surface areas will perform differently (and nor ...


4

Best guesses: One or more cells of the battery is low on water or the plate is collapsing. How old is the battery? Near end of lifespan? A battery can read full voltage, but under load will drop voltage. Are you taking the voltage directly off the battery itself or the cable clamps? Drops to voltage off the battery itself would indicate the need to ...


4

I see two possibilities here: The battery is weak The battery terminals are corroded enough to cause voltage-drop issues, so both battery and alternator are fine but the charging system isn't able to provide full voltage to the battery likewise the starter motor isn't getting the expected voltage from the battery Given that the battery and alternator ...


4

This is much simpler than its being made out to be. The easiest way to do this is to get a simple "clamp meter" that reads electrical current, and clamp it around the positive battery cable while all the accessories you need are turned on. You already know the voltage is 12-14v, so you don't need to measure that. The meter will give you a reading, in Amps,...


2

Just my thought, but I have a similar issue on my race car trailer, which has a huge inverter which runs lights, an air conditioner, a microwave, a refigerator (frozen burritos and healthy hydration liquids) and the DVD player. (These things are essential when racing a vintage car. Say nothing!) My actual point is, I have a bank of 3 deep-cycle batteries ...


2

I assume you're looking for something like this? The key to this is you're looking for a remote starter which happens to provide a low battery protection option. You must have remote start to do what you're asking, and honestly once that's addressed it really isn't a big stretch to add low-voltage protection.


2

Did more research on this and the consensus seems to be that Tacoma's electronics detect the additional current (of the accessory), and drop the voltage automatically as some sort of safety/precaution mechanism. No alerts/lights/errors as a result of this, though. I ended up using an add-a-circuit fuse tap to tap a switched fuse in the engine's fuse block.


2

Remote start is not a separate starting system. It is an electronic control that triggers the existing system to start the engine. Since your car starts by key without issue, I suspect the problem you are having is not related to the car battery or starter itself. Likely what is happening is the battery in your remote is low or dead causing no signal. ...


2

A frayed wire could definitely be the cause. What is the, "wire to the remote starter" and what is it's function? Starting a car, remotely or otherwise, requires a large wire to provide power from the battery to the starter motor, usually through a relay. If you have a bad connection such as wire that's not large enough, wire that is damaged or frayed, or ...


2

I'd say that 16.8 VDC is a bit too high to call "safe." Now to answer the primary question, obviously it depends on the exact vehicle. Different computers and different wiring designs will result in different characteristics. As an example, if your battery is very dead, then putting a 15 VDC trickle on it will read something like 8-10 VDC. You know it's ...


2

To get this off the unanswered question list: There was an intermittent break in the wiring harness near the MAP sensor. I removed the damaged section and lineman-spliced it, and this particular problem disappeared.


2

That is a lot of spark advance. It looks like its sitting at 5-7ish degrees, then pulls up to almost 30 suddenly. Thats way higher than any normal adjustment I've seen. I added my own line onto your graph, and it looks like the voltage drop coincides with the start of the spark advance. Based on this, the fact that the MAP is suddenly blown, and the ...


2

I wouldn't worry too much. You can go a little deeper in checking the system. But you will need a load tester. I wouldn't worry about 0.4v. You could turn on as many loads ad you can. Head lights/hi and low beam, a.c., blower motor, and radio. And check the voltage.


2

It's much cheaper to fix an O2 sensor issue than the consequences of unsuccessfully trying to spoof it, and you will be unsuccessful. Don't do it. If you run an engine too lean it can cause detonation in cylinders, which is the uneven explosion of the fuel-air mixture. Detonation sends shock waves through your cylinder, piston rings, head gasket, valves, ...


2

The answer is that yes, it can be, to some extent, according to battery university. However, the battery should rest for 24 hours, which may be impractical. Note that most cars have a low continuous current drain on the battery. So, ideally, the battery should be disconnected from the car, meaning you lose your radio stations. The other difficulty is ...


2

Use a voltmeter across the battery and an ammeter in series (as mentioned a clampmeter - accurate hopefully) and get the values with all the things running you want. Power is then volts * amps ... Better yet is to have a second battery with a split- charge system - caravaners do this and so do vehicles with electric winches... Edit : added based on ...


2

My car is doing the same - and it's because the demands of lights, heater etc plus the effects of the cold are making the regulator charge the battery more. I have put a multimeter on mine and have seen 15.3V - checked the detail 2 winters ago as i had to replace the original battery (which had a date stamp showing it was 10 years old). In the summer the ...


1

https://en.wikipedia.org/wiki/CAN_bus#CAN_bus_monitor Control Area Network Bus (CanBus) is the data network protocol on modern cars that controls engine, transmission and other vehicle functions. +BM is the positive supply reference input for a bus module on the CAN That voltage must be within certain limits or there is a fault elsewhere in the system. The ...


1

Yes, a bad regulator will cause your motorcycle battery to be overcharged. This is a common failure because of the way motorcycle alternators work. Measure the battery voltage while the engine is running. It should be between 12V and maybe 14.8V max. Now rev up the engine and see if the voltage shoots above that. If it gets to 15 Volts or more, it is ...


1

Here's the diagnostic procedure for a P0328 code from the FSM for the 2002 Subaru Forester. I believe it covers everything. Replacing the knock sensor is trivial, and a new one costs about $75. The knock sensor Is #5 in the diagram below, you have to remove the air cleaner box to access it. It is bolted to the engine block. After the repair, clear the ...


1

While I have lots of opinion, I know of no standard with respect to acceptable voltages to components such as ECUs. Each manufacturer is different. Some ECUs are designed to operate on "28VDC" obviously for markets other than US cars. In general an alternator will provide up to 14.8VDC when charging a lead acid battery. The voltage is slightly ...


1

Doesn't this car have two MAP sensors? See this discussion forum for more information. Seems like one of them involves temperature, so you may have replace them as a pair.


1

i think the absolute max voltage that is farly safe is 14,4 volt,whith todays modern cars and all the computers and sensitiv elecrtonic always use jumper cables that have inbuilt protection. the reason your old mechanic was able to use 24volt to start a 12 volt car was in the past cars did not have sensitive electronic,the worst ting that happened was some ...


1

It seems that 1997 RAV4 has hydraulic power steering, not an electric one. If even there is an electric motor/actuator there, the power would have to drop really low for you to notice, so low that you would have trouble starting the engine next morning. Nothing in the car has even remotely comparable electricity draw as the starter. if the stereo problems ...


1

This sounds like it could be a faulty voltage regulator as you have symptoms of both over-charging and undercharging. Overcharging can fry some components and damage your battery, undercharging can lead to you losing power when you need it. I think that the regulator is actually part of the alternator on this car, you'd have to take the alternator apart to ...


1

Your new battery voltage sounds ok if its been on the charger for that long. Depending on the battery 12.6 - 12.8v is around the right area for an open circuit battery, yours will be higher as its just off the charger by the sounds of it. Once connected to the vehicle and charging the battery voltage should increase to between about 13.8 and 14.7v as the ...


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