Battery or Alternator??

[stealth_grey]

G'day all,

Got a question regarding whether my battery is on the way out or starter is or alternator not functioning...

Ive got a 2000 VX manual wagon that as far as i know still has original battery in it. It starts no worries in the morning and after it has been sitting for some time. The problem is that if i drive for a short distance, stop the car and leave it for a few minutes, then try and restart it, not much happens. It tries to turn over but seems to lack full power. after trying a few times it gets going but sometimes take a few minutes and is becoming a real pain.

Anyone got any ideas whats wrong? I checked the battery, stopped its 12.4V and running is around 14.5 from memory.

Cheers,
Dooners.

[accentstencil]

I'd say the battery is one it's way out. Call into an auto electrician and they can tell in a few minutes if it is the battery.

[Hot-Rod]

i would also say its the battery. Same thing happened to my orginal battery last month. Became harder to start once you turn it off and back on in a short period of time. I changed battery and its all sweet now. Connect a volt meter to your battery pos and neg while starting the car. If it drops a fair few volts then ur battery is dieing.

[commsirac]

Batteries typically get better when they are warm and typically will turn a motor over for hot starts even if they are marginal.
Factors other than the battery causing the hot start problem:

starter motor /soleonoid being affected by heat.
connections in the circuit not all tight and becoming marginal once warm.
tight recond motor, but im guessing you dont have that.

As stated ^, put the voltmeter across the battery while you operate the starter. Battery in good condition should see voltage drop no more than to 10V. Compare this with when it is cold to have some reference point. If your battery is dropping below this, chances are your battery is stuffed, though there is a chance also of a problem in the starter.
If there is minimal voltage drop, like only down to 11V, then that suggests you have a bad contact somewhere which is preventing current flow.

[5ivespeed]

sorry for the thread jack but i dont know whats happening with my car. i drive it and after a while the battery light turns on and my car loses all elec current the blinkers dont work. no gauges except for rev and then it starts to sputter like it has no petrol. then 1 time engine light came on and it stalled. i had to clutch it to get home but dont want to drive it. any ideas?

[LightningVP]

sorry for the thread jack but i dont know whats happening with my car. i drive it and after a while the battery light turns on and my car loses all elec current the blinkers dont work. no gauges except for rev and then it starts to sputter like it has no petrol. then 1 time engine light came on and it stalled. i had to clutch it to get home but dont want to drive it. any ideas?

time to upgrade lol just joking...

Umm, if the lights turn off well before the car does, then I would say your alternator is gone...If it were a fuel problem, the lights wouldn't be affected...But I would go to a battery shop (or an auto sparky) and get them to check the battery...

[BlackVXGTS]

sorry for the thread jack .....

Why be sorry, why not just start your own thread? Your symptoms have nothing to do with the ones mentioned at the start of this thread.

[5ivespeed]

Why be sorry, why not just start your own thread? Your symptoms have nothing to do with the ones mentioned at the start of this thread.

here you go

[Pimpn1]

id be replacing battery as it sounds like it has a dead cell or 2, happened in my toyota corona before it got stolen.. drive it, switch it off.. come back in 5mins dead battery.... when i changed the battery had no problems since....

[south21]

an old fashioned way of checking whether it's alternator or battery is you start the car then while it's idling you disconnect the power lead to the battery if the car keeps running alternator is ok mine will still run with the parking lights on.

[stealth_grey]

Thanks guys,

Well i went to the local auto shop and they did a test on the battery and she a gonna. The bloke was amazed that it would start anythig as he said that the should have been over 460 for that battery and it was sitting on 205. Was a bit beyond me actually.
He also tested the alternator ad it was good as gold, so a big relief. What was the peak draw or whatever he was talking about? It gets stamped on the top of the battery.

Cheers again

[LightningVP]

Not exactly sure myself, but had the same problem...basically the more the better, and longer it will last...I got a re con and it had more draw than a brand new

[commsirac]

Thanks guys,

Well i went to the local auto shop and they did a test on the battery and she a gonna. The bloke was amazed that it would start anythig as he said that the should have been over 460 for that battery and it was sitting on 205. Was a bit beyond me actually.
He also tested the alternator ad it was good as gold, so a big relief. What was the peak draw or whatever he was talking about? It gets stamped on the top of the battery.

Cheers again

Perhaps what he was testing was getting a rough idea of the CCA capacity of the battery. Its the amp rating that a battery can provide at a certain temp for a given time.......its below freezing. I dont think the tester would have any way of extrapolating this for the temperature he tested at.

Anyway, you dont need 460A to start a commodore! 205, if its available will do the job every time, on a battery that is dying this will drop quickly. We get batteries that are rated way over what is needed to start our cars so we have some margin for when the battery is only partially charged and for when it starts to deteriorate. That's generally why a battery with a high cca will last longer, it just takes longer to get to the stage where it drops to the value where it wont turn your motor.
Is putting a truck battery with a very high cca in there worth it, Id say no. The battery costs more and you are carting a lot more weight around, it may not last proportionally longer either...a fault in a cell can occur(new battery needed) just as easily as a smaller battery, go with the manufacturers reccommendation. Though with all things technology changes and a light battery with only 300CCA that's produced in the future may indeed well be suitable for the comm.

[fitz_vt]

you require at least 460 CCA to start a commodore depending on your engine v8's require more but its because of the distrubutorless triple coil high energy starter.... (i know a mouth full isnt it )
mine starts a commodore with 350CCA i think

[sxc_sound]

i had the stocko battery in my vt 430 CCA, (thats an 8 year old battery) and with the multimeter on it while starting it dropped to 4V, it did manage to start still though, i got no idea how. Iv got a 750 cca deep cycle battery now

[stealth_grey]

Thanks for that. The new one seems to have no problems now!

[commsirac]

you require at least 460 to start a commodore depending on your engine v8's require more but its because of the distrubutorless triple coil high energy starter....

The v6 starter is rated at 1.4kW, at 12V, about 120A. Sure the stall current will be much higher.....but another 340A, smoking battery cables!
Its the triple coil attached to the starter that uses the other 340A?, or are you just referrring to the coil packs using 340A,LOL......holy lightning flash batman!

[LightningVP]

The v6 starter is rated at 1.4kW, at 12V, about 120A.
Now what is this triple coil attached to the starter that uses the other 340A?, or are you just referrring to the coil packs using 340A,LOL......holy lightning flash batman!

you called

My old battery was running around 150, would ONLY start the car if I had been driving with nothing else on (no radio, lights etc etc....) or if I jump started...But once it was running the alternator was good enough to keep it going now use the old battery as a "test" battery for my lights before I hook them up

[commsirac]

an old fashioned way of checking whether it's alternator or battery is you start the car then while it's idling you disconnect the power lead to the battery if the car keeps running alternator is ok mine will still run with the parking lights on.

Unfortunately it went out of fashion along with the generator because of the damage it can do to the electrics if you run the car without the load of the battery, please no-one do this or suggest anyone else do it as a problem solving procedure.
All you have to do is put a voltmeter across the battery and compare it with the engine running and not running to establish if the alternator is doing anything!

[Full Spectrum]

Anyone else think the VT-VX's start ****ty at times ?. Like they need more kick to start.

[fitz_vt]

The v6 starter is rated at 1.4kW, at 12V, about 120A. Sure the stall current will be much higher.....but another 340A, smoking battery cables!
Its the triple coil attached to the starter that uses the other 340A?, or are you just referrring to the coil packs using 340A,LOL......holy lightning flash batman!

No... i was talking about 450 CCA

[fitz_vt]

Unfortunately it went out of fashion along with the generator because of the damage it can do to the electrics if you run the car without the load of the battery, please no-one do this or suggest anyone else do it as a problem solving procedure.
All you have to do is put a voltmeter across the battery and compare it with the engine running and not running to establish if the alternator is doing anything!

Yes this will cause severe damage as stated above..... DO NOT USE THIS METHOD, Take it to an auto elec or check the charge rate of the alternator!!!!!!!

[commsirac]

No... i was talking about 450 CCA

You've refuted what I posted in the previous thread....I just dont post rubbish off the top of my head. Please read it carefully and then perhaps you will understand the folly of your statement, "you need 450CCA" to start a commodore.

[danja]

Anyone else think the VT-VX's start ****ty at times ?. Like they need more kick to start.

Sounds like a starter motor getting old (if it's not the battery of course).

If it works, it works.

[Full Spectrum]

Sounds like a starter motor getting old (if it's not the battery of course).

If it works, it works.

Not just mine more every VT-VX i hear start sounds sick when cranking over. Even a few Vy's.