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  • 2005 - 2009 Specific Tech

New Error Code(P0506) - help

  • Thread starter Thread starter Dubl10
  • Start date Start date Aug 21, 2006
D

Dubl10

New Member
Apr 1, 2005
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0
Aug 21, 2006
#1
  • Aug 21, 2006
  • #1
Hello, my car is throwing a CEL again. It's a new error code, which is:

P0506 Idle Control System RPM Lower Than Expected

How can this be fixed, can a tune adjustment be done to fix this or what? Is this something that my tune isn't handling right?

I have an 05 Mustang GT, automatic transmission.

My mods are:

TBS - throttle body spacer
Steeda CAI w/ a Tune, 90mm
SLP Loudmouth exhaust
Kooks Long tube headers w/ catted x-pipe.

In that order of when I put things on.

Now someone mentioned this to me, let me know what everyone else's thoughts are:

I was getting the same code and tried everything to rule out the CIA or the filter the first dealer tried to blame the Code on. Took the car to a different Dealer and they replaced the Throtle Body , under warrenty, becuz it houses the Idle Control part. Been driving the car for two weeks no codes , so far.
Just remember to remove your CIA , if possible, becuz they will try to blame the problem or say VOID Warrenty due to your MODS.

Hey, I had the same problem and the Dealer replaced the Idle Control sensor , which meant replacing the entire throtle body. Just thought I tell you.

Good Luck.
Click to expand...

Is that something I'm going to have to do? instead of just correcting this in a tune? I hope i odn't have to replace my throttle body, that would suck, plus, i don't know if I can get that under warranty, with all my mods, I mean, it's one thing to take out the CAI, but what about the headers, etc..
 

bigcat

start with the upper hole, and if more traction is
May 1, 2005
3,015
1
79
7200 feet
Aug 21, 2006
#2
  • Aug 21, 2006
  • #2
you should be able to raise the idle rpm with the tuner.
 
D

Dubl10

New Member
Apr 1, 2005
49
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0
Aug 22, 2006
#3
  • Aug 22, 2006
  • #3
bigcat said:
you should be able to raise the idle rpm with the tuner.
Click to expand...

that is what i was thinking, i just wish i knew for sure.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Aug 22, 2006
#4
  • Aug 22, 2006
  • #4
you can either raise the idle rpm in the tune and see if that helps.. or try and see if your TB spacer is what is causing the problem.
 
D

Dubl10

New Member
Apr 1, 2005
49
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0
Aug 25, 2006
#5
  • Aug 25, 2006
  • #5
svttech76 said:
you can either raise the idle rpm in the tune and see if that helps.. or try and see if your TB spacer is what is causing the problem.
Click to expand...

the throttle body spacer was my first mod and I've had that on for quite some time up until now. I first got that, then I got the CAI, and then abotu 6 months later i got the headers, etc...

that cel never came on with that code before. So i dont' think it's the TBS. This error code has just recently been thrown ever since i have gotten the headers put on, etc..

but i guess it still could be, i don't know, just don't think it is.
 
D

Dubl10

New Member
Apr 1, 2005
49
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0
Aug 28, 2006
#6
  • Aug 28, 2006
  • #6
*bump

this code never popped up prior to my headers being installed, so i'm wondering if it's just needing a tune adjustment? I can't imagine needing the idle control sensor needing to be replaced.
 

bigcat

start with the upper hole, and if more traction is
May 1, 2005
3,015
1
79
7200 feet
Aug 28, 2006
#7
  • Aug 28, 2006
  • #7
who did you get the tunes from?
 
D

Dubl10

New Member
Apr 1, 2005
49
0
0
Aug 29, 2006
#8
  • Aug 29, 2006
  • #8
bigcat said:
who did you get the tunes from?
Click to expand...

i got the tune from mustangtuning.com, but the car was still running too lean because they set the tune up for the 80mm of the steeda CAI and not the 90mm. So while I was trying to get them to fix my tune, by adjusting it a couple of times, I was over at sctflash.com and Ryan over there helped me out on the first try! he knew exactly what was the problem, so he adjusted my tune to the 90mm and walla! it worked.

Then I got the headers installed, which doesn't require a tune, but now i get this idle lower than expected code, and now some people are telling me that it's the throttle body that needs to be replaced. someone already posted, like i had shown above, where they had to replace the throttle body.

and someone mentioned this too me:

"Contact your tuner and ask him if there is something on the tune that can trigger that or if he has seen it before. If you can't reach anybody then I would put your car to stock. Take off Intake and retune the comp with the stock tune and see if the CEL comes back on and if it does take it to the dealer and if it doesnt then there something wrong with the tune. Just my .02 Good Luck Man"

But i have a bad feeling it's the throttle body, who knows. maybe i only feel that way cause it's the worst case scenario.
 
D

Dubl10

New Member
Apr 1, 2005
49
0
0
Aug 30, 2006
#9
  • Aug 30, 2006
  • #9
Okay, so after I put my long tube headers on, kooks, is when this code started to come up, i would say a few weeks later, maybe a month later. But I checked the way my car was idling, so here is some info for you.

As soon as I start her up, the needle swings up high to 1500 RPM's. It sits there for about 10 seconds maybe, and then it starts to come down to about 1,000.

When I'm driving it, and I come to a stop light, with my foot on the brake, it sits around 800 (can't tell for sure, but that's close, 750 - 900).

Then I checked what it would be when I was in park, just sitting there, when I got to work before turning the car off and it was at 1,000 (when in park).

Is this too high? Or is it maybe too high for what my tune is for, so the idle sensor is throwing that code, as in P0506 Idle Control System RPM Lower Than Expected - meaning, your tune has an idle for this, but the car itself is really idling at this? make sense.
 
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