Need Help Diagnosing Problem

[Hanaldo]

Hey all,

On my way to uni today i noticed my car was being a bit odd. First when i started it up, it started first time and everything but at a lower rev range than usual. Usually when i start it, it fires up to about 1100rpm then drops down to about 1000rpm which is where it idles at. This time it fired up to about 700rpm, dropped to about 600rpm and stayed there for about a second, and then went up to 1000rpm and continued idling normally. I was kinda iffy about it, but didn't think much of it and just pulled off.

Everything was ok while driving, except i noticed my voltmeter was sitting at about 13.8 ~ 13.9, usually it sits between 14 and 14.2. Didn't really think much of that either lol, guess im making a bad habit of that. But when i stopped at a traffic light, after about a minute of sitting there the revs would drop right down to about 600rpm and the car would give a little shudder, then revs went back up to 1000rpm. The thing that made me believe it could be electrical is when the revs dropped, the voltmeter dropped to about 10! and then went back up when the revs went back up. It did this about 4 times on the way to uni, but only when i was stopped at a traffic light and had been sitting there for a bit, and then everything went back to normal. Everything seemed fine otherwise, just the revs and volts dropping and the car giving a bit of a shudder.

Now i just went out side to experiment and see if i could figure it out, and i noticed that when the car is off and i turn the gauges on, the voltmeter reads just below 11 volts, about 10.8 ~ 10.9. Bit odd, usually it sits at about 12 something. Also when my car is off, only one headlight turns on, and i can't turn my highbeams on at all. Might add here that i have HID low beams and high beams, but i used to be able to turn everything on with my car off. All works fine when the car is running though. My guages also do that self checking sweep when you turn them on, and while they are doing this the dash lights flicker. Again works fine when the car is on.

Could this be the end of my batteries life, or possibly the alternator? Or maybe im way off and its something completely different? Any help would be greatly appreciated!!

*EDIT* Should also mention that if i turn my headlights on while the car is off, the voltmeter drops to about 9 volts

Cheers,

Martin

Edited November 11, 2009 by Hanaldo

[GTS-t VSPEC]

Alternator, but cheaper to get your battery checked first.

[stormtrooper]

but didn't think much of it and just pulled off.

Here's your problem... theres a time and a place and in your car is not it, your car knew it and was trying to tell you, not cool...

What Paul said Sounds like alternator/battery issue.

Ah also, HID's wouldn't make a difference much, they use less power than a standard bulb as far as I'm aware. Could also be a spark issue if it's having issues while just sitting at the lights. Normally if you can get the car started even with flat battery/alternator, you're fine until you turn the car off.

Edited November 12, 2009 by stormtrooper

[Hanaldo]

Alternator, but cheaper to get your battery checked first.

So take it to an auto sparky?

Here's your problem... theres a time and a place and in your car is not it, your car knew it and was trying to tell you, not cool...

What Paul said Sounds like alternator/battery issue.

Ah also, HID's wouldn't make a difference much, they use less power than a standard bulb as far as I'm aware. Could also be a spark issue if it's having issues while just sitting at the lights. Normally if you can get the car started even with flat battery/alternator, you're fine until you turn the car off.

Lol i know in my car is probably not the right place, but i didn't get any on the seats!

Someone had told me awhile ago that my alternator may be overcharging my battery, said the voltmeter was reading a bit high while running. Apparently it is supposed to read 14.2 while it is charging the battery, then drop down once the battery has charged. But mine would always read ~14/14.2. I suppose the best bet is to take it to an auto sparky and get them to check my battery and alternator?

HID headlights require 30000 volts to ignite, after that they use less power than a halogen bulb.

[Travo]

what Paul said,

Yep, go to auto sparky and he can test alternator and battery for you.

[br3ndan]

u can test the battery ur self???

Then if thats not the problem, maybe then think about auto sparky.

Wack the battery on a charger if you got one. Or even a multimeter.

If not borrow someones battery and see if it makes a difference.

[Hanaldo]

Yeh ive got a multimeter, will test the battery out myself. But even if the battery is undercharged, it could still be the alternator? If the alternator isn't charging the battery then obviously it is going to have less charge. But i suppose if the alternator wasn't charging it then the battery would be dead... I just don't see how the battery could be causing issues while the car is on, surely once the alternator is spinning then the battery is no longer necessary?

[NISMOGTT]

also make sure the terminals are not loose on the battery as they will wiggle slightly cause odd readings... i would also suggest battery though.

[br3ndan]

Yeh ive got a multimeter, will test the battery out myself. But even if the battery is undercharged, it could still be the alternator? If the alternator isn't charging the battery then obviously it is going to have less charge. But i suppose if the alternator wasn't charging it then the battery would be dead... I just don't see how the battery could be causing issues while the car is on, surely once the alternator is spinning then the battery is no longer necessary?

negative

my euro had a flat battery before. I jump started it. It had shit all power, and gave me flashing lights. For examples the hand brake symbol came on, same with air bag and audio wouldnt run properly. Didnt idle correctly and after about 3-4 mins drive the whole car just shut off without any power at all.

A new battery fixed all of that.

[260tech]

Yes, what stormtrooper said. You must stop doing that in the car. Also, a multimeter will not test your battery however the battery could severely test your multimeter under certain circumstances. Bear that in mind. Any autosparks can quickly load test your battery & alternator. Best bet.

Cheers GW

[DR1FT4]

wrong, you can test your battery with a multimetre, just throw the metre accross it and start it, check the voltage it drops to, if you wonna check amps make sure you connect the multimetre in series with the battery or you you could seriously damage the metre/yourself

[br3ndan]

wrong, you can test your battery with a multimetre, just throw the metre accross it and start it, check the voltage it drops to, if you wonna check amps make sure you connect the multimetre in series with the battery or you you could seriously damage the metre/yourself

agreed

done it many times with different cars

no problem at all with me, the multimetre or the car .

[Yaah31]

man ill come have a look at it tomorow after work see whats up with her

[Yaah31]

k coming from a apprentice sparky here

A Standard Battery When Car id off USING A MULTIMETER should read 12.6 ish volts

When Running Should Read A Tad More Round 13v ish , when idling or around 1000 rpm, Around 3000 rpm multimeter should read 14.2v arounds, If ur alternator Aint making battery Charge to aroun 14 ish volts at around 3000rpm ur alternators the problem

WHen Cranking Over ( So When U Crank Car ( oh yea if u want to get this test without car actually starting ,pull ouy fuel pump relay car wil lstart for a bit due to left over fuel in lines ) But Yea When It Cranks Over the batter reading on the multimeter Should Drop To A MINIMUM of 9.5 a decent battery goes to around 10 11 ish , If The Volts Any LOwer than 9.5 V And Ur BAttery's Stufffed

Edited November 12, 2009 by Yaah31

[Hanaldo]

Cheers Walker, i was going to ask you to check my battery for me anyway Send me a text after work tomorrow yeh

[Hanaldo]

Ok, so Yaah31 came and checked out my car for me, turns out there is nothing wrong with the battery or the alternator lol. Only thing is that there was a volt missing between the alternator and the battery, so there is some resistance somewhere. Don't know what caused the car to do what it was doing though

[Yaah31]

YEa Charge rate was 13.9 -14.1 @ 1500-3000Rpm Which Is Okay

Battery hold rate was okay 12.2V ish ,

Crank Rate Was Sweet 10.2v

Only Liddle Booey Is That '1 Volt Drop' From The Alternator To The Battery ,, Still Think Its The Eart Cable

yea im thinkn where just going to have to change that earth cable looks a bit shit ( previos owner sounds seedy ) , looks way dodgy wires all ovet the joint lol , They May Just Need Cleaing The Termial And Connectors , Buy Some Contact Cleaner ( Or Boiliong Water ) , and a bit of sand paper to get all the greasy Shit Off It , but im still not sure about ur battery man are they standard that size for ur model ??? , it may have high cca but im thinkin she cant hold alot of charge ( due to its size lol ) , oh well , give it time if she gets worse might have to drop her into a QUALIFIED sparky to fix her,

Still Not Sur About That RPM Problem Tho , Im Thinking It Was A Glitch

Edited November 13, 2009 by Yaah31

[R34P3R]

hmm bad idle aye??? did you put a atmo bov.... uhh nvm

all fixed now?

Edited November 13, 2009 by R34P3R

[Yaah31]

hmm bad idle aye??? did you put a atmo bov.... uhh nvm

all fixed now?

only happened once he said i reckon it must have been a glitch , ive had that happen b4 , all i did was pull batteryoff for an our let the ecm like reset , wacked the battery back in , worked liek a charm

[Hanaldo]

Lol fuck you Sunny