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  • SN95 4.6L Mustang Tech

Random hard starting? IAC valve?

  • Thread starter Thread starter 2013 Geee T
  • Start date Start date Apr 26, 2005

2013 Geee T

Founding Member
Sep 25, 2002
805
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Oak Park, CA
Apr 26, 2005
#1
  • Apr 26, 2005
  • #1
Every once in awhile when I start my car it will just turn over and over and then finally start. Could that be an IAC valve issue? I only have 30000 miles on the car.

How often should the PCV valve be replaced too?
 
0

02gtpony

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Apr 13, 2005
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Apr 26, 2005
#2
  • Apr 26, 2005
  • #2
i have an 02 gt with the exact same problem, took it to the dealer and they couldn't figure it out, all they did was reprogram the computer supposedly, and it helped for about a month and now its doing the exact same thing, let me know if you figure it out,
 
C

Cutler03GT

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Sep 25, 2004
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Apr 26, 2005
#3
  • Apr 26, 2005
  • #3
My 03 did it as well, but hasn't in forever. I have a diablo Predator maybe its programming corrected it unitentionaly? And I'm a former Ford Tech. and have had another 03 Stang come in with the same prob and was unable to diagnose it. So I'm stumped to what causes it. I just no that it doesn't do it anymore and am glad cuz it was rather annoying to have remote start and have it not work because of it.
 

COramprat

...I can take it. I think.
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Apr 26, 2005
#4
  • Apr 26, 2005
  • #4
Fuel pressure??? Almost sounds like what happens when you run out of gas. It takes a few turns to get the injectors primed again. Wonder if a fuel pump could give you an intermitant problem? Just guessing.
 
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02gtpony

New Member
Apr 13, 2005
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Apr 26, 2005
#5
  • Apr 26, 2005
  • #5
i have conciderded the fuel pump, it might be the problem, but it started doing that like 15-20k miles after i got it brand new, i don't think fuel pumps go out that quick, but i still plan on changing it, just finding the time to do it,
 

Turbo92PGT

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Feb 17, 2003
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Auburn Washington
Apr 26, 2005
#6
  • Apr 26, 2005
  • #6
When mine did that, it was a tube coming from the fuel pump. Had a small hole in it. The new frpp fuel pump I bought came with it, and all has been well ever since. Make sure you put a new gasket around the fuel pump/sending unit, it should come with the fuel pump. Dont learn the hard way and have yours leak gas.
 
R

rjstaaf

Founding Member
May 31, 2002
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Apr 26, 2005
#7
  • Apr 26, 2005
  • #7
2001 Geee T said:
Every once in awhile when I start my car it will just turn over and over and then finally start. Could that be an IAC valve issue? I only have 30000 miles on the car.

How often should the PCV valve be replaced too?
Click to expand...

How does it run once you get it started? How is the idle? If it were the IAC I would expect idling issues and stalling after it was started.
 

2013 Geee T

Founding Member
Sep 25, 2002
805
5
19
Oak Park, CA
Apr 26, 2005
#8
  • Apr 26, 2005
  • #8
rjstaaf said:
How does it run once you get it started? How is the idle? If it were the IAC I would expect idling issues and stalling after it was started.
Click to expand...


It runs and idles fine. I just remember reading on a post awhile ago that it could be the IAC valve.

Whats involved in doing a fuel pump? Cost?

I hate to replace something thats not the problem and you know the dealer wont do anything unless it does it every time.
 

2013 Geee T

Founding Member
Sep 25, 2002
805
5
19
Oak Park, CA
Apr 26, 2005
#9
  • Apr 26, 2005
  • #9
Wouldnt a bad fuel pump cause problems when the car is running too?
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
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Sea of Tranquility
Apr 26, 2005
#10
  • Apr 26, 2005
  • #10
2001 Geee T said:
It runs and idles fine. I just remember reading on a post awhile ago that it could be the IAC valve.

Whats involved in doing a fuel pump? Cost?

I hate to replace something thats not the problem and you know the dealer wont do anything unless it does it every time.
Click to expand...
My problems with the IAC is the car would start but immediatly die. You could hold the gas and keep it running but as soon as you let off it would die again. Once I got rolling I'd keep it revved and the IAC would eventually "kick" in. You could feel it as there would be a slight smoothing of the engine tone.

The fuel pump is not too expensive but you have to drop the gastank to get to it.
2001 Geee T said:
Wouldnt a bad fuel pump cause problems when the car is running too?
Click to expand...
That is why I was wondering if it could happen intermitantly. It sounds as though fuel is draining away from the injectors cuasing the hard start. Might have the injectors checked out too...possible have some build up that may be causing problems too.
 
R

rjstaaf

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May 31, 2002
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Apr 26, 2005
#11
  • Apr 26, 2005
  • #11
I would do the simple things first. Change the fuel filter if you haven't already. Check your air filter, replace it if need be. Replace the PCV valve (stick with Motorcraft replacement). These are all regular maintenance items anyway and if they haven't been replaced in the 30K miles you have then try them first.
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Apr 26, 2005
#12
  • Apr 26, 2005
  • #12
rjstaaf said:
I would do the simple things first. Change the fuel filter if you haven't already. Check your air filter, replace it if need be. Replace the PCV valve (stick with Motorcraft replacement). These are all regular maintenance items anyway and if they haven't been replaced in the 30K miles you have then try them first.
Click to expand...
Oh yea...good points. Sometimes the simplist of proceedure takes care of the problem.
 
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