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Bad battery causing a misfire? Help

  • Thread starter Thread starter sbelyo
  • Start date Start date Jan 3, 2006
S

sbelyo

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Jan 3, 2006
#1
  • Jan 3, 2006
  • #1
I hadn't driven my 01 auto GT in 5 or 6 days. The battery is original and now has the red dot in the indicator. I drove it this morning and it started to misfire between 1000 and 1500 rpm while driving and on idle. Above 1500 its fine. Before I replace it I just want to see if that happened to anyone else?

I also changed the oil before this happened, but everything is in order there.
 
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sbelyo

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Jan 4, 2006
#2
  • Jan 4, 2006
  • #2
bump....

Could the tps also exhibit these problems?
 

jstreet0204

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Jan 4, 2006
#3
  • Jan 4, 2006
  • #3
If the voltage is low it can cause the misfire codes. Just have the battery tested it may just need a good charge.
 

mrvax

Stay thirsty my friends
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Jan 4, 2006
#4
  • Jan 4, 2006
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See if you can do some highway driving (in the daytime) and keep the rpms up for 1/2 hour. Then re-check the indicator color.
 
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sbelyo

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#5
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It didn't throw any codes yet. It behaved better today only missed a few times. Yesterday there was a ton of traffic so all I did was stop and start and idle. This morning I got the RPM's up for about 20 min. I'll let sears auto check the alternator and battery while I eat lunch. We'll see what happens. I also put a half a can of seafoam in half a tank gas and ran it almost to E. I could've fouled a plug, but I doubt it. If Sears says the battery is fine then I'll hook up my Predator to log 30 min. of data to see if it will tell me what cylinder is missing.
 

timeless2

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Jan 4, 2006
#6
  • Jan 4, 2006
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My bet is that the battery is shot.
 
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sbelyo

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#7
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Battery it is.... Sears took the battery out and tested the alternator. It was functioning fine. The battery is not taking a charge. Well it is 5 yrs old, so I guess it's time for a new one
 

Mike97gt

it doe snot
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Jan 4, 2006
#8
  • Jan 4, 2006
  • #8
i doubt the battery had much too do with the misfire.. but after 5 years it's time too replace it.. esp if the CCa's are really low and it wont hold a charge..

maybe the misfire/hesitation was cuased by the loss of fuel table kam memory when the voltage went low.
 
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sbelyo

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#9
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I suppose that could happen. My next step was to reset the ecu and reload my Predator Tune. I'll change the battery tonight anyway, it's got a dead cell for sure. If it still misses I'l put a data logger on it.
 
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Roger_4.6_96

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#10
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When my alternator was going out i had missfire. Other things are known to make you missfire as well.
 
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sbelyo

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#11
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Roger_4.6_96 said:
When my alternator was going out i had missfire. Other things are known to make you missfire as well.
Click to expand...
I ordered an optima redtop from the local speedshop. It should be in tomorrow. I'll drop it in providing I can see in the dark. I usually ask my 6 yr old son to hold the flash light. This lasts all of 2 min. because he starts shining the light everywhere but where I need it.

I did hook my predator up to view live data and the maf voltage fell in line and the volts were 13.6 but no misses detected but idling rough. Granted I didn't take it for a test drive. I'm going to load the factory tune back in and log the data on the way to work.

Since sears proved to me that the alternator was working and the battery wasn't taking a charge it's not a big deal to replace the battery anyway. It did have a dead cell in it as well
 
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sbelyo

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Jan 6, 2006
#12
  • Jan 6, 2006
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Well it wasn't the battery. I put in an optima red top and it did the same thing after it was warmed up.
 

timeless2

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Did you pull any codes?
 
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sbelyo

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#14
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4u2nv said:
Did you pull any codes?
Click to expand...

Not one blasted code ever....
 
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sbelyo

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Jan 7, 2006
#15
  • Jan 7, 2006
  • #15
It wasnt the battery or alternator or any sensor....

The friggin intake is cracked.... I pulled the first coil on the driver's side this morning and it was full of anti freeze

I guess I'm part of the settlement now
 

bryan0

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Jun 9, 2005
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Jan 7, 2006
#16
  • Jan 7, 2006
  • #16


I hadn't driven my 01 auto GT in 5 or 6 days. The battery is original and now has the red dot in the indicator. I drove it this morning and it started to misfire between 1000 and 1500 rpm while driving and on idle. Above 1500 its fine. Before I replace it I just want to see if that happened to anyone else?
Click to expand...
Oh My God. The EXACT THING happened to me today. The battery light is red. How should I go about checking for cracks in the intake???
 
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