Jump to content
Ultimate Subaru Message Board

voltage meter still goin crazy


Recommended Posts

Define 'up and down'. As previously discussed on the board, fluctuation of these alternators is normal as they are fundamentally weak. Also, older gauges are not as accurate, so it may say 10v, but it's actually12v. Best thing to do is test with a voltmeter at the battery while running. Change the RPMs and see what the actual change is on the meter and see how that compares to the gauge. If you get wild fluctuations (more than say 4 volts difference) then take the alternator back and have them check it. Check your engine to body and battery to body grounds and make sure they are tight and clean. I also remember something about bad grounds behind the IP. Finally, your gauge could actually be going bad.

Link to comment
Share on other sites

... volt gauge is again goin up and down with my RPMs. ...

 

Some Missing information here, but let me Guess in Order to Help you:

  • Does that Behaviour happens only at Idle (Needle Jumpin' a Li'l)?

  • or the Needle Goes Up (I Guess) Near the 18V at High RPM's and Lower when RPM's return to Idle?

in the First Case: Normal Behaviour.

in Second Case: The Alternator's Voltage Regulator is Wrong.

Furthermore, You Need to Define "New Alternator" :

  • Was it a New-to-you Alternator from a Junk Yard?

  • or a Remanufactured / Brand New one?

If it came from a Junk yard, maybe it was Weak and Just got damaged, like the Older one.

If it was a Remanufactured / New one, you must have a Sales Receipt / Guarantee, so you must go Back to the Seller and Ask your Guarantee.

Beside that, there could be some Short Circuit on the Alt's Connections that Might be Causing Damage to the integrated Regulartor Circuit.

Hope this can Help...

Kind Regards.

Link to comment
Share on other sites

I bought the alternator new and installed it about a month ago and it has a 2 year warranty, and yes when it idles around 700 rpms the voltage meter reads around 10 or less and when I get to 3000 rpms the meter reads almost 18. Its not a bad meter needle because while accelerating the dash lights get way brighter and while idling they are way dimmer.

Edited by subinewby
Link to comment
Share on other sites

Had a similar problem to yours except mine pegged out and stuff started coming on by itself. Cut it off and tried it as few minutes later and it was fine. Happened again so I bought a new alternator (remanufactered). Guess what, happened a gain only not quite as bad. The needle climbed up into the red and when I took my foot off the gas to coast to a stop it came out of the red but still high. Turns out after much digging and tearing into my wiring harness to find nothing it was the electrical side of the ignition switch. Replaced it a year ago and it has not occurred again. This may not be your problem but it was mine. Hope that helps you out some.

Link to comment
Share on other sites

I bought the alternator new and installed it about a month ago and it has a 2 year warranty, and yes when it idles around 700 rpms the voltage meter reads around 10 or less and when I get to 3000 rpms the meter reads almost 18. Its not a bad meter needle because while accelerating the dash lights get way brighter and while idling they are way dimmer.

 

 

Define "new"

Link to comment
Share on other sites

OK so the alt I replaced a month ago already went bad. I replaced it again today and both belts snapped off. Took that alt back caus the pully wheel wasnt straight. Put another one in along with the two belts UGGH and the door dinger was goin off but no other power. WTF...so I had some one helping me out and he eventually found a melted wire. anyways its good now until this cheap alternator decides to take a crap on me again. thanks for all the help. Oh and its a remanufactured alternator from costless. I would not advise anyone else to get one they're crap but since its under warranty i'll keep excanging them out till I get money for a good one.

Edited by subinewby
Link to comment
Share on other sites

You get what you pay for, and you got it. NEVER by parts form a large box store PERIOD. For all your time and trouble you could have gotten a quality rebuild from autozone.

 

Large stores and some autoparts stores get cheap rebuilds. They sometimes replace just the bad part and paint it. there is no such thing as standard definition of rebuilt.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...