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2004 cobra vacumm

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Old 05-14-2011, 12:16 PM
  #1  
cobra21987
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Default 2004 cobra vacumm

i was wondering would everybodys vacumm is on there cobra mine is at 26 and my air fuel bounces from 15 1/2 to 17 1/2 and idles like ****. I am also getting a po135 po155 po171 and po174 code. I cleaned the mass air and the idle control valve just to eliminate that any other ideas guys i dont wanna just start sticking money into it without knowing any other ideas thanks
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Old 05-14-2011, 06:42 PM
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derockgt
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my vacumm is at 19-20.X and A/F at idle is at 14.7 then goes down to about 11.4-11.7 at WOT. did it just start? do you have a dyno tune? can tune? pulley?
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Old 05-14-2011, 10:27 PM
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ttoney
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P0171/0174 indicates that the long term fuel trims have reached a maximum (should be somewhere around 30-35%). Fuel trims are how much fuel the PCM adds or subtracts. 0171/0174 indicates that the engine is running lean, meaning that outside air is getting past the mass air sensor.

1. Check your PCV for eaking or deteriorated PCV tube connection
2. Check you vacuum lines are connected or deteriorating

Pretty sure you have a vacuum leak either way.
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Old 05-15-2011, 02:32 AM
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cobra21987
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could it be the dfpe cause my fuel pressure drops right to zero soon as i turn my car off and the car idles smooth till in warms up a little and the idle bounce dont happen all the time either idk
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Old 05-15-2011, 10:37 AM
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Blackvenom01
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holy crap your running freaking lean dude be very very careful take that thing right away to a dyno tuner and get that figured out before you blow your motor

also sometimes cleaning the IAC isnt good enough but yes look for leaks like ttoney said

no it shouldnt drop fuel right away!!
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Old 05-15-2011, 11:13 AM
  #6  
cobra21987
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could it be the dfpe sensor at all
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Old 05-15-2011, 10:41 PM
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cobra21987
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Changed the front o2 and still has idle problems screw it I'll just bring it in tommarow to the tuner
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