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Strange issue with new DD... please help!

  • Thread starter Thread starter 1991notchbackLX
  • Start date Start date Apr 25, 2010

1991notchbackLX

Active Member
Dec 25, 2007
1,483
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48
New York
Apr 25, 2010
#1
  • Apr 25, 2010
  • #1
Okay, so last night i used the Diablo Predator that came with my new (to me) 1999 GT to re-flash the computer to run on the 87 octane tune. I decided to do this to save some money on gas. I did it late last night, let the car run for about 10 minutes and then shut it off until this morning.

I got in the car this morning and drove it for about 20 minutes, shut it off for about 2 minutes, then started it back up and now have a strange hanging idle issue while in neutral. With the clutch all the way to the floor or in neutral the car suddenly idles at 2000+ RPM. With the car in gear with the clutch half depressed it will idle at a normal RPM, but as you can imagine this gets old very quickly.

What could cause this?? Do you all think this has something to do with the Diablo tune? This car is my daily driver now so I really need all the help I can get in getting this problem fixed as quickly and cheaply as possible. Please post up with any advice and opinions. Thanks in advance for the help!

Chris
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
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Sea of Tranquility
Apr 25, 2010
#2
  • Apr 25, 2010
  • #2
Might be a glitch in the tune. Depending on the method used to program whether a dyno or mail order is could be something lacking in the later. I had a mail order tune originally on my Xcal 2 and on the 87 tune it would spit/sputter and hesitate under acceleration. Or you could try to reflash the tune again and see if it clears up.
 

ChillPhatCat

20+ Year Stangneter
Apr 22, 2002
409
65
48
Syracuse, NY
Apr 25, 2010
#3
  • Apr 25, 2010
  • #3
1991notchbackLX said:
With the car in gear with the clutch half depressed it will idle at a normal RPM, but as you can imagine this gets old very quickly.
Click to expand...

Don't do this, you're burning the clutch.
 

Red35th

Member
Apr 18, 2003
609
2
19
Houston, TX
Apr 25, 2010
#4
  • Apr 25, 2010
  • #4
I think the first thing to do is re-flash it back to stock and see if that helps.

Beyond that, I'm not too familiar with 5-speeds, but look at the IAC to see if it's maybe hanging open.
 

1991notchbackLX

Active Member
Dec 25, 2007
1,483
47
48
New York
Apr 27, 2010
#5
  • Apr 27, 2010
  • #5
Thanks for the opinions guys. I'm gonna go out there now and flash the computer back to stock and see what that does (if anything). Any other suggestions out there in cyberspace?
 
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