So...need a little help here:

Basically I noticed this issue when I had the air on (and radio?), and deck power would cut out, and then the entire car would shutter, and turn off for a second, but then turn back on.

I assumed the battery was getting drained when the accessories on, so I assumed the alternator was the culprit.

I took a DMM to the battery (Brand new - approx. 12.4 volts).
With the car running, no air on - 13.9-14.0 volts.
When I turn the air on (not all the way) - it would read 13.7-13.8 volts, but once the compressor turned ON, it would drop to 13.2.

Basically, my conclusion is I am assuming the alternator is "OK", but is not keeping up when all the accessories are on?

Also, when I crank the car to start, it has a very slow starting condition (even with the battery charged at 12.5 volts). Is there any way a faulty compressor would cause a slow starting condition?

Im really stuck here guys, could use some help

Thanks!



Edit: 1999 Jeep Cherokee 4x4 4.0 I6

 

dang, nobody???

 

The batt should be at 12.4-12.65 I believe with the vehicle off. With the vehicle on the alternator should be charging at 13.5-14v and above 2,000rpm should be at 14-14.5v.

Have your starter tested if you can to see if it is causing a drain and the hard starting. Make sure all of your connections from the alternator are tight and clean... same with the battery and starter.

 

^ X2...

 

Thanks for the help...


would the starter cause a drain after the car is already running? Also, as I said, once the compressor kicks on, the voltage drops signicantly. Alternator connections are good

 

Absolutely... Even on my '82 Kawasaki motorcycle, the starter was bad and causing resistance at the positive terminal of the starter... it wouldn't let my bike charge over 12.5v... replaced the starter and I was back over 14v. If the starter IS the cause and you fix it, your compressor kicking on should not make the volts drop as much... but since it is drawing current, it will drop some.

 

so update: I had the charging system tested at two different AutoZone's (the first guy was clueless).

So at the first one, with the air off, the voltage read 13.9 and everything "Passed"
Second test: with the AC fully on, voltage: 13.2-13.4 and everything "Passed"

They both said everything is good...still not sure about this

Any thoughts guys?

 

Can you explain this? I'm not saying it's not true...I just don't understand it. If the starter isn't engaged, how could it be a drain on the battery? Maybe it was a bad connection somewhere and the connection was corrected in the process of changing the starter?

 

I have a similar problem on my 97 xj when it's cold out it takes around 10 to 15 seconds of cranking for it to fire but when it is warm out it it fires right up I have changed the plugs wires cap and rotor button to no effect and I can't find the culprit.

 

I will give it a shot... The starter was pretty well destroyed internally (brushes and commutator) and the parts were arcing. Anytime the starter was engaged it would suck all but the smallest amount of juice from the battery and barely crank the engine. The drain while running was a bad internal solenoid ground and the internals of the starter didn't help with the cranking... I apologize, I should have clarified better what my issue was.

 

i have a 96 2.5L and i have slow cranking because my AC compressor is frozen and the clutch wont fully disengage lol hope that helps you a little

 

Pretty sure you can get an A/C bypass belt from most auto parts stores... If they don't have one most of the time you can measure, with a string, all of your pulley's minus the A/C compressor and find a suitable belt length.

 

update: got alternator cleaned up...realized battery cable ends at terminals are pretty corroded. Ordered some kwips cables, gonna put them in soon. Hopefully that should help

 

Or get an AC pulley delete.