Can anyhelp me on this please?

Question

Hi,My Subaru,when I start the car my voltage meter reads between 10 and 11 orless sometimes which makes my car weak, but when i go over 3 and halfthousand revs my voltage shoots up to 13 amd running fine      This is a right pain because sometimes my battery goes flat leaving tobump the car of leads but the battery is fine.Has anyone else accoured a similar problem?ThanksCeri

mulder · Accepted Answer

Could be a weak battery and/or alternator. You say the battery is "fine" but have you actually had it load-tested?If you have a voltmeter (not the one in your car, a handheld one such as a multitester), connect it directly to the battery terminals. With the car not running and the key off, the battery should read 12.5V. If it reads less it is either not fully charged or it's NG. When cranking the engine to start the battery voltage should not drop below about 10V, again if it does this indicates a weak battery. With the engine running at idle with no electrical accessories turned on, the voltage should read approximately 13.5-14.5V. If it's lower, the alternator may not be charging sufficiently. If it's higher, it's overcharging.If you aren't able to do these tests yourself, take it to a shop that can fully evaluate the electrical system.outrated wrote:

outrated · Answer

Hi,Thanks m8 will take it to a local outfit.Ceri

Edward Hayes · Answer

AutoZone will do a voltage charging test for you free.

mulder · Answer

Don't think he has Autozone in the UK :)Edward Hayes wrote:

Hallraker · Answer

Those poor people in the UK. No wonder our ancestors left there (and other countries.) No Autozones! :)

Back on topic, that's how my Subaru behaved when the alternator bit the dust. Bad voltage regulator in my case. Take my advice, if you DIY, *do not* buy a cheap alternator. You're only asking for more headaches later.

-Matt

Leo Lichtman · Answer

^^^^^^^^^^^^^^^Kragen does this also.  If you walk in with an alternator, they willtest it right at the counter.  They will also roll a test stand outinto the parking lot and test your entire charging system--the onlycost is for any parts you end up buying.

Can anyhelp me on this please?

Join the Discussion

Didn't find your answer?