Wierd Voltage Drop?
#16
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It's really not good to run it without the battery, especially reving it. Leaves you computer and everything else vulnerable to any little voltage spike that the battery would have dampened. At least that's the way I see it. I think my AC compressor clutch has a wire there that can be unplugged. Pretty sure there is no harm in that. Might be helpful to rule that out.
#17
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It's really not good to run it without the battery, especially reving it. Leaves you computer and everything else vulnerable to any little voltage spike that the battery would have dampened. At least that's the way I see it. I think my AC compressor clutch has a wire there that can be unplugged. Pretty sure there is no harm in that. Might be helpful to rule that out.
#19
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It doesn't have to squeel or make any noise when it slips.
Putting any kind of load on the system, blower, lights etc causes it to need to put more back in the battery. It will slip then, even if it's not making any noise.
The reason it was hard to start is last time you were driving it you had something turned on, the extra load drained the battery down. When you went to start it the battery was low already.
Such a simple thing - find where the belt runs the longest between pulleys. Twist the belt If you can twist it 90 degrees it's too loose! 45 degrees max.
Running it like that mav have glazed the belt - it will always slip no matter how tight. You've been letting it slip since last summer when the AC was too much load. It's probably dead by now.
Get a QUALITY belt from NAPA or Car Quest. Chinese belts from Autozone or those cheapie junk stores will slip even when new.
I'm really surprised that so many "experts" don't have a clue!
Putting any kind of load on the system, blower, lights etc causes it to need to put more back in the battery. It will slip then, even if it's not making any noise.
The reason it was hard to start is last time you were driving it you had something turned on, the extra load drained the battery down. When you went to start it the battery was low already.
Such a simple thing - find where the belt runs the longest between pulleys. Twist the belt If you can twist it 90 degrees it's too loose! 45 degrees max.
Running it like that mav have glazed the belt - it will always slip no matter how tight. You've been letting it slip since last summer when the AC was too much load. It's probably dead by now.
Get a QUALITY belt from NAPA or Car Quest. Chinese belts from Autozone or those cheapie junk stores will slip even when new.
I'm really surprised that so many "experts" don't have a clue!
#20
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Year: 1999
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ok ill try it thanx, no need to hate on these people that were trying to help me tho i asked for opinions
#21
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well your alternator is good. and ^that guy^ with the "twist the belt" and the "power drain" stuff....
the only time the battery power should ever be lowered is at immediate crank. after the immediate crank all power supplied to the vehicle comes from the alternator. Thats why the positive battery cable runs straight to the starter. The ancient myths of hurting your computers while taking the positive cable off is crazy because of the previous statement. if your jeep runs without that positive cable your alternator and belt are just fine. the truck would sputter or die if not. An alternator is built to supply power to the truck and recharge the battery. most vehicles on the market now have soo many bells and whistles that some alternators (like my cherokee chief) have a high output alternator just for that.
the power loss sounds like it is idle sensor related. the idle sensor is slowing the speed of the motor and telling the fuel system to run slower, causing a slow in firing, and overall RPM's which can lead to your belt not spinning fast enough to make your stock spec alternator charge fast enough.
I would recommend a troubleshooting guide for that or ask a trusted mechanic. im just going off of 5 years of auto shop experience. im not SAE cert or anything haha. its just stuff i picked up along the way.
the only time the battery power should ever be lowered is at immediate crank. after the immediate crank all power supplied to the vehicle comes from the alternator. Thats why the positive battery cable runs straight to the starter. The ancient myths of hurting your computers while taking the positive cable off is crazy because of the previous statement. if your jeep runs without that positive cable your alternator and belt are just fine. the truck would sputter or die if not. An alternator is built to supply power to the truck and recharge the battery. most vehicles on the market now have soo many bells and whistles that some alternators (like my cherokee chief) have a high output alternator just for that.
the power loss sounds like it is idle sensor related. the idle sensor is slowing the speed of the motor and telling the fuel system to run slower, causing a slow in firing, and overall RPM's which can lead to your belt not spinning fast enough to make your stock spec alternator charge fast enough.
I would recommend a troubleshooting guide for that or ask a trusted mechanic. im just going off of 5 years of auto shop experience. im not SAE cert or anything haha. its just stuff i picked up along the way.
#22
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You are right - the alternator provides all the energy required to run the vehicle after it starts - or should when it's working right.
The computer/ignition needs about 10-12 amps.
blower another 10-15 amps,
lights another 10-12.
That's at least 30+ Amps PLUS whatever it takes to refill the battery back up to full charge. (A battery can only accept about 30 Amps max to recharge.) It takes a few minutes for the battery to be refilled.
That's alot of energy the belt has to transfer. Plus turn on the AC - that takes another 2-4 horsepower for that already overworked belt to handle. That's why some vehicles use 2 tandem belts.
You can buy a tension gauge for between 30-150 dollars to do the same thing the twist method does.
BTW - what idle sensor? There isn't one per-se.
5 years of school - vs. 47 years and owning 4 successful repair shops, including one specializing in high performance and dyno tuning. Keep up the good work!
OP - let us know how it comes out!
The computer/ignition needs about 10-12 amps.
blower another 10-15 amps,
lights another 10-12.
That's at least 30+ Amps PLUS whatever it takes to refill the battery back up to full charge. (A battery can only accept about 30 Amps max to recharge.) It takes a few minutes for the battery to be refilled.
That's alot of energy the belt has to transfer. Plus turn on the AC - that takes another 2-4 horsepower for that already overworked belt to handle. That's why some vehicles use 2 tandem belts.
You can buy a tension gauge for between 30-150 dollars to do the same thing the twist method does.
BTW - what idle sensor? There isn't one per-se.
5 years of school - vs. 47 years and owning 4 successful repair shops, including one specializing in high performance and dyno tuning. Keep up the good work!
OP - let us know how it comes out!
#23
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Year: 1986
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there is a comp on some of the models that automatically adjusts the amount of gas-air that is fired through the injectors. im not sure what ones have it. a friend of mine with an 97 had a problem with horsepower drop and he said thats what he did.
all together though,this problem has to be electrically related. that is the only explanation.
all together though,this problem has to be electrically related. that is the only explanation.
#24
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Year: 1999
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hate to jump in on this post but dose anyone know if a battery with a cell going bad can cause this problem and other ele. probmems
#25
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other than that i cant help you there
#27
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When you use the defroster, the AC kicks on the reduce moisture. My guess without seeing it is that somehow this is causing your belt to slip, and thus lose alternator output. You may have a bad AC compressor which is putting a drag on the serp belt.
#28
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#30
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Green - to clarify things - you get va squeel when the AC is on.
But you still experience this when the AC is OFF?
"""""The voltage drop problem is the same. I've narrowed down its ways.
Any heater setting, no problem
Defroster no headlights, little drop
Defroster and headlights, big drop
Defroster headlights and off road lights, significant power loss"""""
If the belt slips the alternator CANNOT provide enough to power things properly. It has to supplement it with battery power. That's why the voltage drop.
It loses power because the computer senses something's wrong and goes into "limp in mode.
Get a good tight belt on it - you'll see! If it still has trouble with the AC ON then that's a different issue altogether.
I've heard on other forums the Optima's have problems since they moved to Mexico. The good Die Hard's are the best now - American made!
But you still experience this when the AC is OFF?
"""""The voltage drop problem is the same. I've narrowed down its ways.
Any heater setting, no problem
Defroster no headlights, little drop
Defroster and headlights, big drop
Defroster headlights and off road lights, significant power loss"""""
If the belt slips the alternator CANNOT provide enough to power things properly. It has to supplement it with battery power. That's why the voltage drop.
It loses power because the computer senses something's wrong and goes into "limp in mode.
Get a good tight belt on it - you'll see! If it still has trouble with the AC ON then that's a different issue altogether.
I've heard on other forums the Optima's have problems since they moved to Mexico. The good Die Hard's are the best now - American made!