ECU reprogramming
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ECU reprogramming
Random Q -- On an OBII 97-98 993, is there a way to visually determine if an ECU has been reflashed, reprogrammed or modified in some way? Like on the circuit board or something...e.g., solder in a particular place, etc. If not visual, my presumption is that some sort of specialized computer should be used, yes?
Thanks much.
Thanks much.
RL Technical Advisor
Joined: May 2001
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From: Portland Oregon
Random Q -- On an OBII 97-98 993, is there a way to visually determine if an ECU has been reflashed, reprogrammed or modified in some way? Like on the circuit board or something...e.g., solder in a particular place, etc. If not visual, my presumption is that some sort of specialized computer should be used, yes?
Thanks much.
Thanks much.
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The shear bolts that hold down the metal shield over the ECU and that hold down the ECU itself are a one-time deal, they have to be drilled out or notched with a dremel to remove them and they can't be reused. Usually these shear bolts are replaced with new metric bolts so if you see those, the ECU has almost surely been out of the car and likely replaced or reprogrammed.
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The shear bolts that hold down the metal shield over the ECU and that hold down the ECU itself are a one-time deal, they have to be drilled out or notched with a dremel to remove them and they can't be reused. Usually these shear bolts are replaced with new metric bolts so if you see those, the ECU has almost surely been out of the car and likely replaced or reprogrammed.
Of course I installed allen head metrics upon reinstallation, but the lack of shear bolts is not much of an indicator that the ECU has been replaced or reprogrammed; only that its been removed at one time.
I could have used new shear bolts upon reinstallation.
Last edited by nine9six; Jan 24, 2015 at 02:25 PM.
RL Technical Advisor
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From: Portland Oregon
While chasing down a some gremlins, I removed my ECU and shear bolts; but I do not have a reflashed chip.
Of course I installed allen head metrics upon reinstallation, but the lack of shear bolts is not much of an indicator that the ECU has been replaced or reprogrammed; only that its been removed at one time. I could have used new shear bolts upon reinstallation.
Of course I installed allen head metrics upon reinstallation, but the lack of shear bolts is not much of an indicator that the ECU has been replaced or reprogrammed; only that its been removed at one time. I could have used new shear bolts upon reinstallation.
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While chasing down a some gremlins, I removed my ECU and shear bolts; but I do not have a reflashed chip.
Of course I installed allen head metrics upon reinstallation, but the lack of shear bolts is not much of an indicator that the ECU has been replaced or reprogrammed; only that its been removed at one time. I could have used new shear bolts upon reinstallation.
Of course I installed allen head metrics upon reinstallation, but the lack of shear bolts is not much of an indicator that the ECU has been replaced or reprogrammed; only that its been removed at one time. I could have used new shear bolts upon reinstallation.
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While VA993Dreamer was parroting your earlier statement, he missed the most important aspect (the tabs) and wound up with a statement that seemed unlikely...
the ECU has almost surely been out of the car and likely replaced or reprogrammed.
...and thats about it.
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Agreed!
While VA993Dreamer was parroting your earlier statement, he missed the most important aspect (the tabs) and wound up with a statement that seemed unlikely...
I was simply trying to point out that the lack of shear bolts, while a probable that the ECU has been removed, it is not any kind of indicator that it was likely replaced or reprogrammed.
...and thats about it.
While VA993Dreamer was parroting your earlier statement, he missed the most important aspect (the tabs) and wound up with a statement that seemed unlikely...
I was simply trying to point out that the lack of shear bolts, while a probable that the ECU has been removed, it is not any kind of indicator that it was likely replaced or reprogrammed.
...and thats about it.
Signs that the ECU has been 1)removed, 2)replaced 3)re-programmed...or all of the above:
-ECU cover tabs look like they've been messed with (surely the best indicator, but not the ONLY indicator based on Steve's comment. Note that I, nor nine9six, mentioned this until Steve did and that's why he's the expert and not me, and certainly not nine9six)
-Shear bolts don't look original-perhaps they were replaced with new shear bolts, allen bolts, or metric bolts
And that's about it.
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From: Portland Oregon
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From: Oregon
While nine9six seems to have some challenges comprehending simple concepts, let's review some key points for the benefit of the OP and perhaps nine9six can follow along slowly and get it:
Signs that the ECU has been 1)removed, 2)replaced 3)re-programmed...or all of the above:
-ECU cover tabs look like they've been messed with (surely the best indicator, but not the ONLY indicator based on Steve's comment. Note that I, nor nine9six, mentioned this until Steve did and that's why he's the expert and not me, and certainly not nine9six)
-Shear bolts don't look original-perhaps they were replaced with new shear bolts, allen bolts, or metric bolts
And that's about it.
Signs that the ECU has been 1)removed, 2)replaced 3)re-programmed...or all of the above:
-ECU cover tabs look like they've been messed with (surely the best indicator, but not the ONLY indicator based on Steve's comment. Note that I, nor nine9six, mentioned this until Steve did and that's why he's the expert and not me, and certainly not nine9six)
-Shear bolts don't look original-perhaps they were replaced with new shear bolts, allen bolts, or metric bolts
And that's about it.
I did not intend to step on your toes over your inability to communicate clearly; only to clarify that the statement was at a minimum partially inaccurate. My apologies.
I understand that you have a Rennsport reflashed ECU, and that now upon removal and reinstallation, you are at least a master at identifying reflashed, replaced, touched, futzed with, breathed or otherwise gazed upon ECU's.
Unfortunately. these incredible technical skills you have amassed, has little to do with one's ability to clearly articulate said knowledge in text.
Please pardon my attempts to clarify. Mea culpa, I
to your knowledge, skills and abilities. 
You da man! Baaaahaahaaa 
RL Technical Advisor
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From: Portland Oregon
Boys boys,...time for a group hug.
We all share the passion for these incredible machines and I hope we can all meet each other in September at the Rennsport Reunion for a beer.
We all share the passion for these incredible machines and I hope we can all meet each other in September at the Rennsport Reunion for a beer.
Race Car
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From: Miamah, La Florida
I think most of us know that 996 likes to have the last word in most threads but we need that sometimes, especially when el QC stays quiet!
