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HP Tuners please look @ this problem

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Old Sep 27, 2004 | 05:49 PM
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Default HP Tuners please look @ this problem

Any HP tuners ran into this. Everytime I try to do the simplest tweek to the stock tune the car revs up to about 2000rpm @ start-up and the idle surges between 800 and 1000. I put the stock tune back....everything is fine. Add 1* of timing @ 5000rpm...same problem. Then I downloaded a tune from a board member that wasn't stock..and the car cranks and idles fine. But if I tweek that tune ANY, same problem. The shop that did my dyno tune said they have tuned tons of LS1's and never seen this before. Any insite would be greatly appreciated.

Jason
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Old Sep 27, 2004 | 06:39 PM
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Originally Posted by JayStew
Any HP tuners ran into this. Everytime I try to do the simplest tweek to the stock tune the car revs up to about 2000rpm @ start-up and the idle surges between 800 and 1000. I put the stock tune back....everything is fine. Add 1* of timing @ 5000rpm...same problem. Then I downloaded a tune from a board member that wasn't stock..and the car cranks and idles fine. But if I tweek that tune ANY, same problem. The shop that did my dyno tune said they have tuned tons of LS1's and never seen this before. Any insite would be greatly appreciated.

Jason
My truck did that every time I installed a new pcm with a new tune. HAvent done any tuning of my own yet, but I will let you know.
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Old Sep 27, 2004 | 07:16 PM
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What version are you using?

What table are you using to add 1 degree at 5000 RPM's?
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Old Sep 27, 2004 | 07:50 PM
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Originally Posted by Magnus
What version are you using?

What table are you using to add 1 degree at 5000 RPM's?
Version 1.4.5 brand new

I was just using that as an example. Any change, no matter how small, makes it act up. But with the borrowed tune it worked fine until I tried to tweek it, then it acted up as well. I went back to the original borrowed tune and no problems.
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Old Sep 27, 2004 | 07:57 PM
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Got my answer.

Originally Posted by DY
I found the same thing... easy and quick fix

In the engine spark advance screen whenever you click save it changes the "main spark table select" MPH from 256 to 0.0 ....

the way around it is to put in 255, it seems to only zero out when set to 256


Once I found this my car idled perfectly and now I everyone in the area has idle envy
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Old Sep 27, 2004 | 09:10 PM
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Originally Posted by JayStew
Got my answer.


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Cool , just got my Vette back together from yanking the cats off and it was doing just like you described
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Old Sep 28, 2004 | 06:56 PM
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This issue has been fixed and will be distributed in our 1.5 release.

Sorry for the troubles.
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