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THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 Performance Upgrade
Leading reported evidence
Replace failed
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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Discussions that performed work without a confirmed outcome
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Performed · outcome unconfirmed · Original poster
failed and was replaced by one of the local SoCal Porsche dealers that I work
Leading evidence: 'Replace failed' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Recommend against doing such' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
We don't do ANY type of DME mods and highly recommend against doing such.
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Suggestion · Original poster
But having been in the Porsche repair business both at the independent and
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Suggestion · Original poster
whether because of a physical mod or a flashing, the repair shop will mostly likely start by
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Suggestion · Original poster
There're enough problems with local flaky Porsche repair shops
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20 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T020439Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Here're pictures of a performance upgrade done to a 996 DME ECM which
failed and was replaced by one of the local SoCal Porsche dealers that I work
with.
The 1st is the front side of the DME ECM which looks O.K.
The back side is the Mickey Mouse mod.
The final picture is the modified back cover to make room for the Mickey Mouse
chip attachment.
A very costly upgrade for the 996 owner, i.e. the initial mod (~$750-$1000) and
the replacement (>$1000).
Why is it a "mickey mouse" mod? Piggy backing a chip is done in many applications to modify the program in a chip. Perhaps there was a problem with the installation that caused the DME to fail.
"why didn't you just post "buy one of our mods"
No!!!!!!!!!
"It sounds like a jab at this mod."
You got it.
We don't do ANY type of DME mods and highly recommend against doing such.
If you do a Rennlist search, you'll find that's the case. Even simple changes such
as an EPROM R/R via a socketed chip we discourage. The thread was posted
as insightful info for those that allow someone "possession" of their DME ECM
for a performance upgrade.
The worst is the "piggy-back" type because they usually "butcher" the PCB, and thus
are very unreliable because of this. Furthermore, OBDII cars (late 993s and up)
have enough problems wthout some Mickey Mouse mod to provide questionable
performance enhancement.
The bottom line is that Porsche/Bosch tunes their engines for the best all-around
performance even when one considers the typical hyperbole from the tuners.
For those that wish to waste their money or are unconcerned about reliability,
buy another DME ECM to keep as a spare when you get stuck in a remote location
and the immobilizer fails to communicate with the DME ECM and the engine won't
start.
Folks need to read the threads a little more carefully to grasp the real meaning and intent behind the particular posting before your "ready-fire-aim" comments. This one was a warning against butchering your DME, not an attempt to sell a product or service.
Thanks Loren for the info.
chuck
Loren, maybe it's a stupid question but I'm confused with the abbreviations, so does this mean that you do not recommend any ECU upgrade (re-programming) like GIAC or do we talk here about different mods?
That's one interpretation; maybe the correct one. That ECU doesn't look like top quality work, for sure.
But you've never heard of negative advertising based on fear, uncertainty, and doubt?
Bill
"it's a stupid question but I'm confused with the abbreviations, so does this mean that you do not recommend any ECU upgrade (re-programming) like GIAC"
That's correct! I get slammed a lot because of this view, as one can tell by reading some Rennlist
posts and my website. But having been in the Porsche repair business both at the independent and
dealer levels for over 15 years, I dislike seeing Porsche owners get "taken down the path" and
having to deal with costly repairs in the long term.
Here's a 993 DME ECM damaged by a performance mod:
https://rennlist.com/forums/993-forum/338261-993-dme-modification-for-tuning.html
"What is the percentage of people with these failures?"
Do a poll! I know I wouldn't let my Porsche be modified by someone in a remote location
with little to no recourse. There're enough problems with local flaky Porsche repair shops
that screw-up the car by doing a minor service. These late cars are so complex and problematic
even without mods.
Bottom line: Are the potential problems really worth the marginal, at best, performance gain?
if your car has a running issuse and you have a "modified" ecu, under warrenty or not expect the techs first step to be replaceing the dme (2800$ os so) out of your pocket and thats just to know that the dme is not the problem.
"if your car has a running issuse and you have a "modified" ecu, under warrenty or not expect the techs first step to be replaceing the dme (2800$ os so) out of your pocket and thats just to know that the dme is not the problem."
That's it exactly!
I'll speak up on this one as an EE with 30 years experience.
I would not want a board modded like that in my car. A car is one of the harshest environments that exists for electronics. There are only a couple of other environments that are worse. And a Porsche, or any stiffly suspended sports car is the worst of the car environments.
Vibration which probably tops 20 G's. Temperature from -20F to 150F.
That soldered on socket is likely to lift traces right off that board in this environment, imagine the collateral damage that happens then.
One the flipside, I guess modders like GIAC are doing flash downloads nowadays, so this discussion is probably moot for our 996's, since they dont need this kind of "Mickey Mouse" mod.
"One the flipside, I guess modders like GIAC are doing flash downloads nowadays, so this discussion is probably moot for our 996's, since they dont need this kind of "Mickey Mouse" mod."
That's basically the same issue without the added mechanical PCB issues, i.e. These tuners
with their mods "push" some of the maps to get the "feel" performance that the OBDII system
has continual faults or the readiness states don't set. I've seen other cases where the OBDII
communications no longer functions properly after the flash. Again, if the car has a problem
whether because of a physical mod or a flashing, the repair shop will mostly likely start by
replacing the DME ECM as mentioned previously. Either way, in the long term it's a loser.
I'm an EE as well. Mainly ASIC and FPGA designs, but I've done my share of PCB's. I agree with Loren and Larry. I would only trust those PCB cluges in a benign lab environment for debug purposes only. Certainly not in an automotive environment. And that other link that Loren provided is one of the worst looking things I've ever seen. My university design projects looked better than that.
And I have to agree with the "chipping" issues. Being a conservative engineer, I would be worried that these new engine mappings might sacrifice reliability. Maybe there are areas or certain engines that have the extra design margin. I certainly don't know. Does the aftermarket company know? Maybe not, maybe so. I think that's a valid question to ask of them if you are considering such a mod. But, I personally can't afford to second guess the Porsche engineers on my engineering salary.
This is a source reference. Confirm exact model applicability in the original material.
