I'll keep it simple. If i charge the battery for a few hours i can get quite a few starts out of the car if i drive it abit. However if the car sits for awhile the car will not start without a jump. Even after the jump if i drive the car for awhile the car will not start without a jump or unless i do a slow charge for a few hours on the battery. The car does not shut down while its being driven however. I took it to 2 places today to get it looked at the official battery test passed at both autozone and advance discount however Advance persisted that the issue was the battery saying AC delcos are crap only they only last 3 years. I then took it to advance who tested and came back to say the voltage regulator was bad. This all seemed to happen maybe 1 week after i installed the new MPX lighweight pulley which may or may not be coincidence. Thoughts opinions would be greatly appreciated. Autozone says they cant get the part in so i would need to go through GM for a new alternator. Thanks again for your wisdom cobalt sages.

 

light weight pullies are garbage.

could be just a bad cell in the battery or a bad alt. go to a mom&pop store have them check both.

 

if it doesn't lose voltage driving your alternator isn't bad. starter, well it's starting so it's not that. so that leaves battery... and lightweight pullies are garbage as said

 

simple to check, get a multimeter, start ur car, check the voltage on the batt, it its anything less than 14v while car is running ur altinator is bad, ur altinator may be just bad enough that it cant keep the batt charged. my forklift at work is doing the same thing, as long as i dont use the lights it still starts. its is charging at 13.5 which is enough to work, but not enough to charge and maintain the batt

 

At idle you might not get the full 14v.

 

generally is 14.4 when starting and 13.8 running on cobalts

get a meter put it on the battery and try and start the car. see where the voltage goes when its "cranking"

 

It's the battery.

 

Had a very duh moment on this one here. So my RPD tells the voltages it send to the battery. It varied between 11.9 -12.5 v. SO my room mate decided to unplug the battery while the car ran and we watched the RPD. Nothing changed in the voltages. We plugged the battery back in and went for a drive. Flooring it the voltages went down to about 11.4. upon releasing the throttle it went back to the fluctuating 11.9 -12.5

 

I'm certain it's the battery had to replace my battery from the exact same things. Check out some of these ODYSSEY Batteries

 

so ur seeing 125 max with the car on?... also i wouldnt really trust the rpd

 

check voltage at battery terminals while running as said...if it's not high 13's or 14's its the alternator.. your car can run on the battery for a bit while driving. has this issue with my honda accord a few months ago.

 

every time iv measured its 14 or more at idle, should be that way if its not there is a problem

 

if u do see high 13s it should be poping up to 14 and back to high 13s at least

if thats how low they are that is ur altinator. get it changed. its not making enough juice to charge the batt or keep it charged, the stuff running off the batt is draining it faster then the altinator can charge at those voltages, iv had enough altinators go on me to know this already, and if u dont change the altinator as soon as possible it will kill ur battery. and if it would be ur battery thats bad, which its not, but just in case it may happen one day, change the batt as soon as u can cause it can kill the altinator but having it constantly trying to charge the battery. that happened to me once to. to be safe change both, but if someone tested the batt and its good, just change the altinator

 

depends on how through the test they did on the batt was... u can have a battery with 1 bad cell that will look good and act ok but when u crank voltage drops way down. hard to catch unless u know what ur looking for

regardless unless hes using a good meter or something halfway reliable then not much more then guesses going on here

 

Why not try a different battery? Why make this more complicated then it needs to be. I've had this issue on my car my battery was **** put a new optima in (wish i would've known about Odysseys then) and all was well.

 

if the car is running and u measure voltage at the batt ull get 14v regardless if the batt is bad or not, if he isnt its the altinator plain and simple. iv done this many times before with bad batt and good altinator and vice versa

 

it"s the battery!!!

 

Ok so i took the car in last friday I took the car into GM. They replaced the battery and i made it almost 20 miles before turning off the car only to find my battery was dead once more. Upon a quick phone call they were quick to say "Oops we forgot to put the new battery in!" I take the car back and they swap in a new battery. I drive her for a whole week often finding myself needing to turn it off and back on. She hesistates abit but always starts. Well today ended that streak upon driving to the local 7-11 for a quick drink she had died. Tomorrow she goes back in.

 

yup thats bad alt or some sort of drain....

 

guess it wasnt the battery after all lol

 

well a week later and its doing it again. Friend seems to think the pully is killing the alternator. Thoughts on this? Prob gonna put it back to stock and see if that helps. if not ill take it back to chevy

 

what pulley?

 

Win some, lose some.

 

its the mpx lightweight

 

is it under or overdrive?