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car stalls on start up

  • Thread starter Thread starter carbed 85 gt
  • Start date Start date Jan 29, 2007

carbed 85 gt

New Member
Mar 20, 2003
121
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0
Honolulu HI
Jan 29, 2007
#1
  • Jan 29, 2007
  • #1
Hey all I am fighting this problem when my car is warm it starts right up but dies immediatley. I have to feed it some throttle and slowly let it come down to idle and it drives fine. I have no surging at lights but if I bump the trottle and let it close too quickly it dies. This is and auto car with the trickflow hci.

I pulled the codes and got 33(egr) and 87??? I have fuel pressure but get this code?
 

stangman11

Member
Feb 27, 2006
220
3
19
New Jersey
Jan 29, 2007
#2
  • Jan 29, 2007
  • #2
most likely its your IAC (idle air control) there notorious for going on the 5.0s id take that out first check the passage ways and see how much its gunked up. If its bad sometimes u can simply fix it by cleaning it out with some brake clean and be ok. If you clean it and it gets louder and the problem is still present your gonna need a new IAC
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Jan 29, 2007
#3
  • Jan 29, 2007
  • #3
maby check or change the fuel filter if you don't know when the last time it was changed
 

carbed 85 gt

New Member
Mar 20, 2003
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Honolulu HI
Feb 4, 2007
#4
  • Feb 4, 2007
  • #4
I replaced the fuel filter and have new gaskets installed on the lower intake manifold. Still stalls on start up and idles fine once idle comes down with assitance of accelerator pedal. I pulled the codes again and dont have the 87 code. But it pops up from time to time. Where should I look for the 87 code?
 

jrichker

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Feb 4, 2007
#5
  • Feb 4, 2007
  • #5
Code 87 – fuel pump primary circuit failure. The fuel pump lost power while the engine was running. Check fuel pump relay, check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check the other side of inertia switch for +12 volts.

To help troubleshoot the 87 code, follow this link for a wiring diagram for 89-93 cars http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp

For 79-88 cars use, http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp


Your IAC & idle need some attention. See "Help me create the Surging Idle Checklist" at http://forums.stangnet.com/showthread.php?t=534062
for help with your idle problems. The first post contains all the updates to the fixes. I continue to update it as more people post fixes or ask questions.
 

carbed 85 gt

New Member
Mar 20, 2003
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Honolulu HI
Feb 4, 2007
#6
  • Feb 4, 2007
  • #6
But the car starts and run, and I have fuel pressure. i drive the car every day and this code has come up about a month ago, This code comes up every once in a while.
 

jrichker

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#7
  • Feb 5, 2007
  • #7
carbed 85 gt said:
But the car starts and run, and I have fuel pressure. i drive the car every day and this code has come up about a month ago, This code comes up every once in a while.
Click to expand...

It is probably caused by a bad connection in the relay socket or the relay is intermittent. Clean the relay socket with electical contact cleaner or non-flammable brake parts cleaner.
 
C

C6AE

Member
Mar 22, 2004
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Ma.
Feb 5, 2007
#8
  • Feb 5, 2007
  • #8
My '91 was doing that and it was the IAC valve. I got some throttle body cleaner and got all the crud out of it. No more problems
 
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