hey...i dont know if anyone here is overly good with the cars charging system...but here she goes.

95 max GLE...car is not charging correctly...battery shows 12.5V at idle...can rev it up to low 13's, but no higher. i know that when everything is normal, i do get the 14.3-14.4V that i like. alternator tested fine at a shop the other day, but im kinda thinking its an interm. alternator problem...battery tests fine as well. alt is 4 months old, battery is 2 weeks old. ok...this is what else ive found. both the power wire from the alternator to the battery and the ground from the alternator to the battery appear fine...minimal resistance. so...if the alt. is good...the battery is good...and the wires between the two are good...how come its not working correctly? i have audible alternator whine, and if i have more than just headlights/heat/radio on and what not, it will draw my battery down enough so my car will shut off...if i keep the RPM's up, itll charge the system enough so it doesnt die. i do have a kicker 1200.1 amp with 2x12l7 subs...but they are not hooked up now and i still have problems.

any ideas? just a bad alternator or what? the only other thing that i have come across that COULD be a problem is a small oil leak on the pass side of the engine which could lead to oil getting on the belt...possibly causing it to slip which would i assume lead to me not getting all the charge even if the alt is working correctly.

anyway...any help would be appreciated. i have some knowledge with this stuff, so please only honest and informative replies...and yes, my battery terminals are tight!

 

Well if the belt was slipping you would most probably hear it squealing.

Sounds like a bad alternator to me... where did you get the alternator you put in 2 months ago from?

 

i agree about that i should be able to hear the belt slipping...just thought i would throw that in there...as you prolly know, alternator is a fun job on the max...spent a day putting a new one in, and found it afterwords that it was bad out of the box...didnt have anymore time, so i brought it to a shop and had them throw one in real quick...NAPA alternator...i know i know...but hey, its all i could do at the time!

 

Sometimes you gotta do what you got to do... for parts that are not easily replaced or could leave me stranded, I stick to OEM - for exactly this reason. However, I know of at least one member who used an OEM alternator and had it fail within a year.. so the grass isn't always greener....

 

anyone with any ideas?

 

Does the Voltage/Battery light on the dash ever trip while the car is running? When the car is off, how much current is pulling across the battery (use a clamp multimeter)?

 

no battery light issues in the dash...that operates correctly...and i have nominal current draw...like 0.013V. i also have a 4 gauge ground from my battery to the chasi to help with ground issues...

 

anyone with any ideas?

 

Your regulator is going bad - integral part of the alternator. I had that problem. Charging seemed fine but never enough to keep the battery topped off - eventually the battery will die and you will be stranded - time for a new alternator.

 

Current is measured in Amps.

It really does sound like your voltage regulator is failing. From your description, it seems that your battery is supplying all of the voltage when at idle and low revs, and even at high revs it's still doing more than it's normal share. Unfortunetly it looks like you're going to have to replace your alternator again.

I'd try to stick with OEM for the replacement alternator.

 

thats what i kinda figured...once i figure out what it was, ill let everyone know.

 

The wining noise is also a clue that your alt. is no good.

 

my 2 cents says the alternator is nfg.

 

Unhook the power wire to your amp at the battery. See if this makes things better. Your system might be drawing too much power.

I saw this problem before in one of the cars I fixed up. A 91 maxima. What was happening was that the cooling fans would come on and never turn off. This drew the battery down so much that it would just shut off the car.

So check your cooling fans too. The problem is one of two things. There is either too much current draw or not enough current generation. Or both.

 

my "system is completely disconnected...has been for weeks. anyway...im sure the alt took a **** this weekend...car stopped running, and the classic 3 lights came on (battery, brake, abs) so i took it up to the shop that installed the alt (before i knew what the heck i was doing) and they can deal with it for me free of charge of course thanx for the inputs, and as i said before...ill let you all know what they found