Jump to content
SAU Community

Recommended Posts

Hi all,

i fitted a brand new battery this morning, turned her over and all was fine.

not 30 minutes later i tried to start it again and it was flat.....clutch started it and drove off. about 10 minutes down the road the car started to choke....the revs began to bounce and within 30 seconds the car cut out.....i pulled over and tried to crank it.....flat.

i pulled out a charged battery and jumped started it.....disconnected the jumper.....and fine for 20 seconds......then revs started to bounce again....then cut out again....

i swapped the batteries....and the she started fine and ran ok......i then disconnected the battery as i didnt want it to drain again......i was then able to drive the car for 10 minutes home....

i noticed on the way home that the battery light in the dash was on.....firstly what does that light mean? and what do you think i am faced with?

im thinking alternator is cactus....but why?? nothing has changed since i drove it last....

also i just changed front bar....could the fog lights, even tho they are visibly off, somehow be on and sucking power? nothing else has changed....

list of things i need answered...

1. what does the battery light in dash mean?

2. could it be my alternator?

3. how hard is it to change an alternator?

4. fog lights?

thanks guys!!

  • Nope 1
Link to comment
https://www.sau.com.au/forums/topic/338337-new-battery-flat-in-30-minutes/
Share on other sites

Hi all,

i fitted a brand new battery this morning, turned her over and all was fine.

not 30 minutes later i tried to start it again and it was flat.....clutch started it and drove off. about 10 minutes down the road the car started to choke....the revs began to bounce and within 30 seconds the car cut out.....i pulled over and tried to crank it.....flat.

i pulled out a charged battery and jumped started it.....disconnected the jumper.....and fine for 20 seconds......then revs started to bounce again....then cut out again....

i swapped the batteries....and the she started fine and ran ok......i then disconnected the battery as i didnt want it to drain again......i was then able to drive the car for 10 minutes home....

i noticed on the way home that the battery light in the dash was on.....firstly what does that light mean? and what do you think i am faced with?

im thinking alternator is cactus....but why?? nothing has changed since i drove it last....

also i just changed front bar....could the fog lights, even tho they are visibly off, somehow be on and sucking power? nothing else has changed....

list of things i need answered...

1. what does the battery light in dash mean?

2. could it be my alternator?

3. how hard is it to change an alternator?

4. fog lights?

thanks guys!!

Is the alternater changing the battery

im definitely no expert but id say that the battery isnt getting charged from the alternator...but i got no idea how to test it....

im charging the battery again and will try it in the car again...

im definitely no expert but id say that the battery isnt getting charged from the alternator...but i got no idea how to test it....

im charging the battery again and will try it in the car again...

mm maybe google it, there is a way but i don't wanna tell you the wrong way!

The RED battery light means there's a problem with the battery / charge circuit. The alternator is probably frizzed. The battery might last longer if you turned the frikken fog lights off (they're for foggy conditions, hence the name).

If you don't know how to test the alternator, try a search.

Fog lights are never on, just fitted a new front bar and then this started. Might check the earthing, and then check the alternator.

Anyone know how to change an alternator? Anyone done it?

1. what does the battery light in dash mean?Battery isn't charging.

2. could it be my alternator?Yes most likely

3. how hard is it to change an alternator?Not hard. Its very easy

4. fog lights?Doubt it to be the cause

will invest in a multimeter.....read up on how to test....

could it be a dud battery? i bought it new...but who knows what kind of condition its in....anyone else had incidents with new batteries dying straight away???

will invest in a multimeter.....read up on how to test....

could it be a dud battery? i bought it new...but who knows what kind of condition its in....anyone else had incidents with new batteries dying straight away???

Biggest point that makes everyone say alternator is the fact that you were driving it and it still died. If a car is started and the alternator works fine you pretty much don't need a battery there it will run off the alternator

^^ +1 battery dying usually consists of it dropping a cell and will only retain 10 volts instead of 12 but once its started alternator will cover it. battery light doesnt usually come on if its a dud battery apart from taking a couple extra seconds to go off sometimes on start up. check fuses if havent already

changed to 2nd hand alternator. no change at all....

still has battery light....still no charge from alternator (ie reads 11.8v at idle)

what else should i check? could i just have the worse luck or could something else be stuffed?

does anyone know the electrics work? could there be a fault elsewere??

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I neglected to respond to this previously. Get it up to 100 psi, and then you'll be OK.
    • I agree with everything else, except (and I'm rethinking this as it wasn't setup how my brain first though) if the sensor is at the end of a hose which is how it has been recommended to isolate it from vibrations, then if that line had a small hole in, I could foresee potentially (not a fluid dynamic specialist) the ability for it to see a lower pressure at the sensor. But thinking through, said sensor was in the actual block, HOWEVER it was also the sensor itself that broke, so oil pressure may not have been fully reaching the sensor still. So I'm still in my same theory.   However, I 100% would be saying COOL THE OIL DOWN if it's at 125c. That would be an epic concern of mine.   Im now thinking as you did Brad that the knock detection is likely due to the bearings giving a bit more noise as pressure dropped away. Kinkstah, drop your oil, and get a sample of it (as you're draining it) and send it off for analysis.
    • I myself AM TOTALLY UNPREPARED TO BELIEVE that the load is higher on the track than on the dyno. If it is not happening on the dyno, I cannot see it happening on the track. The difference you are seeing is because it is hot on the track, and I am pretty sure your tuner is not belting the crap out of it on teh dyno when it starts to get hot. The only way that being hot on the track can lead to real ping, that I can think of, is if you are getting more oil (from mist in the inlet tract, or going up past the oil control rings) reducing the effective octane rating of the fuel and causing ping that way. Yeah, nah. Look at this graph which I will helpfully show you zoomed back in. As an engineer, I look at the difference in viscocity at (in your case, 125°C) and say "they're all the same number". Even though those lines are not completely collapsed down onto each other, the oil grades you are talking about (40, 50 and 60) are teh top three lines (150, 220 and 320) and as far as I am concerned, there is not enough difference between them at that temperature to be meaningful. The viscosity of 60 at 125°C is teh same as 40 at 100°C. You should not operate it under high load at high temperature. That is purely because the only way they can achieve their emissions numbers is with thin-arse oil in it, so they have to tell you to put thin oil in it for the street. They know that no-one can drive the car & engine hard enough on the street to reach the operating regime that demands the actual correct oil that the engine needs on the track. And so they tell you to put that oil in for the track. Find a way to get more air into it, or, more likely, out of it. Or add a water spray for when it's hot. Or something.   As to the leak --- a small leak that cannot cause near catastrophic volume loss in a few seconds cannot cause a low pressure condition in the engine. If the leak is large enough to drop oil pressure, then you will only get one or two shots at it before the sump is drained.
    • So..... it's going to be a heater hose or other coolant hose at the rear of the head/plenum. Or it's going to be one of the welch plugs on the back of the motor, which is a motor out thing to fix.
    • The oil pressure sensor for logging, does it happen to be the one that was slowly breaking out of the oil block? If it is,I would be ignoring your logs. You had a leak at the sensor which would mean it can't read accurately. It's a small hole at the sensor, and you had a small hole just before it, meaning you could have lost significant pressure reading.   As for brakes, if it's just fluid getting old, you won't necessarily end up with air sitting in the line. Bleed a shit tonne of fluid through so you effectively replace it and go again. Oh and, pay close attention to the pressure gauge while on track!
×
×
  • Create New...