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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Idle surging then engine dies

  • Thread starter Thread starter 795.0pacecar
  • Start date Start date Feb 13, 2006

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
Feb 13, 2006
#1
  • Feb 13, 2006
  • #1
Well my idle surges between 500rpms and 900 rpms, then works its way to 200rpms and 1000 rpms, then dies on occation, it also dies when Im coming to a stop and I push in the clutch every now and again. 40% of the time it idles fine although slightly wavy. I have replaced the AIC and the TPS is new and came with the trottle body, I have tried just about ever idle surging remedy I've read on this site, that includes setting the idle with the AIC unplugged and resetting the TPS voltage. I've heard there is an adjustible bypass valve I could buy that goes inline with the the AIC that could fix my problem. I dont think there are any vacuum leaks either. I have another TPS I could try but Im not sure that would do anything to help. The car ran and idled perfectly before I put the heads/intake/ and rockers on my car. Mods are in the sig. Fuel pressure is at 41psi and is just on the edge of lean, plugs are white with a slightly brown tint to them.
I got some codes from the comp.
KOEO self test
34 - Not sure if this would effect the idle
67 - I never wired the neutral safety switch when I did the swap
81 - deleted emmissions equipment
82 - deleted emmissions
87 - fuel pump is not wired through the comp, it is wired through the ignition switch instead
Continuous memory
14 - I had the TFI tested and it tested fine, so I replaced the Stator, it seems to help alittle but not much.

I bought a code reader and I plan on clearing the codes in the morning then doing a KOEO and KOER test tomorrow night.

Any help is greatly appriciated. I cant have this thing dieing on me in traffic all the time.
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Feb 13, 2006
#2
  • Feb 13, 2006
  • #2
check the maf?

I had the same problem and then cleaned out the iac really well and it kinda helped, but it really helped when i took the maf apart and cleaned all the connections. Was corrosion on there and that musta done it. Then when I just put my 70mm in last week, took care of the problem completely, now it idles perfect. Just a thought, otherwise I don't know
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
Feb 13, 2006
#3
  • Feb 13, 2006
  • #3
My engine is speed density. I did clean the IAC real well and it helped alittle, so I bought a new AIC and it was about the same, so Im thinkin thats not the problem.
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
0
37
Jersey Shore
Feb 13, 2006
#4
  • Feb 13, 2006
  • #4
Idk if this would help but it has to do about the whiteness of the plugs http://forums.stangnet.com/showthread.php?t=615169...Try putting the fuel pressure back down to stock and reset the comp...and see what you get after the KOER test.........BTW what kind of injectors/maf do u have?
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
Feb 13, 2006
#5
  • Feb 13, 2006
  • #5
19lb injectors. Remember this is speed density, there is no MAF and I hear SD doesn't like anything but stock injectors unless you get a tune.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
Feb 13, 2006
#6
  • Feb 13, 2006
  • #6
See the sticky "Help me create the Surging Idle Checklist" at the top of the forum for help with your idle problems. The first post in the sticky has almost all the details you need.
 

95GTV8

New Member
Jul 25, 2005
386
3
0
Washington State
Feb 13, 2006
#7
  • Feb 13, 2006
  • #7
check for vac leaks.
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
Feb 13, 2006
#8
  • Feb 13, 2006
  • #8
Well I figured it out. Apparently the TPS sensor that came with my professional products 65mm tb is a piece of crap. Even though I could set it to the right voltage it still wasn't working right. I swapped it out for the one that was on the original tb that came off the old intake and now it works fine. No more surging.
 

willys1

Active Member
Dec 2, 2003
1,004
1
36
New Jersey
Feb 13, 2006
#9
  • Feb 13, 2006
  • #9
yeah check the sticky,its got alot of info!!
 
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