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Electrical Revs at idle running like crap

  • Thread starter Thread starter sienna1212
  • Start date Start date Jan 5, 2013

sienna1212

New Member
Jan 4, 2013
5
1
1
Jan 5, 2013
#1
  • Jan 5, 2013
  • #1
I have a 2005 GT. Last year my passenger window started going wonky, Its not the motor as I can bust into the panel, press a certain spot and it works. The door was hit, and replaced with a used door. Months later engine light on, throwing codes for misfire. Replaced plugs, codes go away, month later same codes. It was not charging, replaced alternator. Good as new...

Flash forward 1 year later. Woke to dead battery... replaced battery, next day throwing codes again, I would bet money that they are the same codes. Car is revving at idle ! Has no guts, feels so sluggish, feels as if it will stall, but hasn't yet. Nothing is dimming. Has a faint gas smell while driving.

My pop is a retired mechanic, but old school stuff. We are not up to speed with sensors and such.

Our plan for the am is to run codes, check voltage, and go from there. I have heard cam shaft sensor, shaker drawing power, is it possible the window has a short? We put the old battery on a charge and it is coming back to life, alternator again? Coil packs ? Help this is my only set of wheels and am at a loss.

Donna
 

Vegas

Member
Dec 23, 2012
32
0
7
Las Vegas, Nevada
Jan 5, 2013
#2
  • Jan 5, 2013
  • #2
sounds like alternator , do you have after market stereo amp?
 
R

Redfire281

Member
Nov 28, 2007
39
0
7
Jan 5, 2013
#3
  • Jan 5, 2013
  • #3
You'll need to write the codes down and tell us what that are. Otherwise, we'll have to do a process of elimination which could get expensive for you. The passenger door issue may not be related depending on what "wonky" means and what certain spot you're pressing in order to make it work. It might be related if it is an open circuit that is draining your electrical system. Reving at idle could be your TPS is faulty, or the wiring is frayed and you're getting intermittent contact, or your MAF sensor and air filter are dirty or the intake tube is loose, or your throttle body has oil residual from blow-by, etc. But these are things your pop can check because they are common to old school stuff. For him it's just a matter of what is still mechanical and what is now fly-by-wire.
 

sienna1212

New Member
Jan 4, 2013
5
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1
Jan 5, 2013
#4
  • Jan 5, 2013
  • #4
Hi Tested the alternator today with everything on and its failing. Then we ran the code and it came up P0506. Going to trade in the alternator on Monday, as its less than a year old. Then we will take the door apart and see if we can fix the window. Not sure if its related or a coincidence. I have a stock shaker 500 with 6 disc changer, and have read about those who have their car sit and have battery drain from the amp, I would think that would have shown up earlier though and this problem started once the car was 6 years old. will see what the alternator replacement does.
 

sienna1212

New Member
Jan 4, 2013
5
1
1
Jan 14, 2013
#5
  • Jan 14, 2013
  • #5
Replaced alternator, fixed window... ran great for a day. Now same hesitation, revs at idle, ran like crap today, code is back ! HELP. Could this be a second bad alternator?
 
R

racerraj

Founding Member
Dec 17, 2001
493
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39
Dickson, TN
Jan 14, 2013
#6
  • Jan 14, 2013
  • #6
Sounds to me like throttle body needs to cleaned or replaced.
http://forums.themustangsource.com/f739/trouble-code-p0506-454620/
 
Reactions: sienna1212

sienna1212

New Member
Jan 4, 2013
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Jan 14, 2013
#7
  • Jan 14, 2013
  • #7
Thanks, will pass info along to my dad. But would that affect voltage? It drops when I turn on accessories while running. We have been using rebuilt alternators as money is tight.
 

gearheadboy

15 Year Member
Jan 15, 2003
1,425
177
84
Greencastle Pa
Jan 14, 2013
#8
  • Jan 14, 2013
  • #8
If you turn on everything and are at idle it may be normal for it to have trouble keeping up. Make sure it is fully charged on a trickle charger, terminals are clean and tight. Does it have underdrive pulleys? That would make it worse. How are you determining that the alternator is failing?
 

sienna1212

New Member
Jan 4, 2013
5
1
1
Feb 2, 2013
#9
  • Feb 2, 2013
  • #9
racerraj said:
Sounds to me like throttle body needs to cleaned or replaced.
http://forums.themustangsource.com/f739/trouble-code-p0506-454620/
Click to expand...
Just wanted to say Thank you ! Your advice was spot on, after checking that the new alternator was fine, We finally took throttle body off today, cleaned it and BAM, code disappeared and car is running great ! All for the cost of a can of throttle cleaner.
 
Reactions: racerraj
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