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  • 1996 - 2004 SN95 Mustang -General/Talk-
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Please help with codes.....

  • Thread starter Thread starter Unreal281
  • Start date Start date Mar 18, 2006

Unreal281

Member
Dec 18, 2004
98
0
6
Mar 18, 2006
#1
  • Mar 18, 2006
  • #1
Sup, all of my mods are in my sig...i'm throwing a:
* P0420 _catalyst efficiency below threshold (bank 1)_
* P1507 _manf cntrl veh. spd. Idle Speed Control Auxilary Inputs_
codes were read at advance auto parts with a handheld device.....
what do these two codes mean?



-thanx
 

Pearl02

Member
Nov 27, 2004
496
0
16
Kansas City
Mar 19, 2006
#2
  • Mar 19, 2006
  • #2
I think the 1507 code has to do with your IAC. Can't help you with the other code. I haven't come across that one. Pearl02.
 

MaxedGT

Member
Mar 31, 2005
304
0
17
Surrey BC Canada
Mar 19, 2006
#3
  • Mar 19, 2006
  • #3
The p0420 is because your cat is gone, on bank 1. The other code I don't know.
It sounds like an IAC fault.
 

MaxedGT

Member
Mar 31, 2005
304
0
17
Surrey BC Canada
Mar 19, 2006
#4
  • Mar 19, 2006
  • #4
Off topic. I just installed BBK off road x-pipe, and it sounds like I've got an exhaust leak, but I don't. If it wasn't for that, it sound great. How do you like the sound of your exhaust? Do you get the same sound, on moderate acceleration?
On topic: using mill eliminaters? The Bank one mil, is probably shot. BBk recommends switching the two mil eliminaters if it throws codes, claiming this sometimes helps.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Mar 19, 2006
#5
  • Mar 19, 2006
  • #5
yeah your mil is probally gone. switch them.

p1507 is a IAC valve underspeed error. this is cused by the rpm's droping below what is commanded by the PCM.

the pcm has no feedback on if the IAC itself is opening right, so it can only tell if the idle speed is not what is being commanded based on IAC opening percentage.
 

MaxedGT

Member
Mar 31, 2005
304
0
17
Surrey BC Canada
Mar 19, 2006
#6
  • Mar 19, 2006
  • #6
By switching them I mean just side to side.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Mar 19, 2006
#7
  • Mar 19, 2006
  • #7
MaxedGT said:
By switching them I mean just side to side.
Click to expand...


yeah I know what you mean. you can try it and see if the code moves to the other bank. then you know for sure the mil is bad.

and for the other code you can try cleaning the IAC valve out
 

Unreal281

Member
Dec 18, 2004
98
0
6
Mar 19, 2006
#8
  • Mar 19, 2006
  • #8
Maxed......yea i LOVE the sound of mine.....have to admit it is a bit raspy but i believe you have to get used to it.....it almost makes a machine gun sound between 2500-3200....but i got used to it....mine sounds a BIT better IMO because of my long tubes.....i dunno dude...its an aquired sound basically....any other questions you got....just hit me on the AIM at unrealca281....later bro....and for the verdict....are we just saying that i need to get two bbk MILs and clean out my IAC? how do i clean that out? thanx guys...
 

MaxedGT

Member
Mar 31, 2005
304
0
17
Surrey BC Canada
Mar 19, 2006
#9
  • Mar 19, 2006
  • #9
Unreal281 said:
Maxed......yea i LOVE the sound of mine.....have to admit it is a bit raspy but i believe you have to get used to it.....it almost makes a machine gun sound between 2500-3200....but i got used to it....mine sounds a BIT better IMO because of my long tubes.....i dunno dude...its an aquired sound basically....any other questions you got....just hit me on the AIM at unrealca281....later bro....and for the verdict....are we just saying that i need to get two bbk MILs and clean out my IAC? how do i clean that out? thanx guys...
Click to expand...
I think I might need time, as you say, to get used to the sound of mine. Took me a little while to get used to the cat back when I first put that on too.
As far as the mil eliminaters, try just switching them, from one side to the other and see if it still throws a cat code. If not you're good. If It does, you need new mil eliminater, or you could go with a programmer such as the Diablo preditor, or SCT.
The IAC, just take it off. spray it with throttle body cleaner and wipe it clean.
Do the same to it's port. Take off the intake duct and open the throttle and spray it down and wipe it clean inside as well.
 
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