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starting problem, need help

  • Thread starter Thread starter b1gp1mp1n247
  • Start date Start date Mar 19, 2004
B

b1gp1mp1n247

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Feb 19, 2004
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Pittsbrugh, PA
Mar 19, 2004
#1
  • Mar 19, 2004
  • #1
i know people have complained about this a million times on here and i have searched all the posts and tried everything . my problem is on my 90 GT whenever the car is cold it wont start right up. i have to hit the gas to keep it going but after it warms up its fine. i can turn it off and start it with no problems after its warmed up. i have tried everything that everyone talks about in the other posts that i have searched. cleaned throttle body, fuel pressure is at 35, changed 02 sensors, plugs, rotor, cap, wires, fuel filter, fuel pump, new intake manifold gasket, vacuum hoses are new and not leaking under the intake manifold, and i even added a AFPR. and also the tps is set at 98.5. now my only thing left is that i noticed when checking for vacuum leaks, i noticed that the only vacuum line connected from all the lines in passenger side engine bay is the red line that runs to the back of the intake and to the FPR. smog is gone so those vacuum lines are plugged. could there be any other vacuum lines that need connected that are plugged? i get a reading of about 10 from my vacuum gauge when car is in Drive and it holds steady at about 18 at 2500rpm. the only code that was pulled was one for the 02 sensors so i changed them. i have been putting endless amounts of money into trying to solve this problem with no luck, somebody please help and give suggestions on anything to try. i am open to hear anything. thanks in advance and i apologize for the long post but i wanted to give as much info as possible. thanks again
 

93 LX

Founding Member
Jun 2, 2000
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Norwalk, CA.
Mar 19, 2004
#2
  • Mar 19, 2004
  • #2
This must be a typo. TPS setting 98.5? You must mean 0.985 vdc. At 1 volt the computer will see the TPS is opening.

Did you replace the IAC on the side of the TB assembly. Mine was carboned up and I had to replace it to work properly.

-a
 
B

b1gp1mp1n247

New Member
Feb 19, 2004
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Pittsbrugh, PA
Mar 19, 2004
#3
  • Mar 19, 2004
  • #3
i meant .985 my bad. and yes i have replaced it. any other suggestions its killin me!
 

jrichker

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Mar 10, 2000
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Dublin GA
Mar 19, 2004
#4
  • Mar 19, 2004
  • #4
Vacuum is low at 10", you have a vacuum leak. You should see 16"-19" at idle in netural with a stock cam and no forced induction.
 
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b1gp1mp1n247

New Member
Feb 19, 2004
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Pittsbrugh, PA
Mar 21, 2004
#5
  • Mar 21, 2004
  • #5
...
 
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QBstang87

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Jun 14, 2002
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Montgomery Village, Maryland
Mar 21, 2004
#6
  • Mar 21, 2004
  • #6
ect sensor? there wasn't a code in it for that? that sounds like it'd play a big role when you say cold vs warm starts. and vacuum too, but vacuum shouldn't make a difference in cold vs. warm, it should always be a problem.
 
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