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General Sticky ECU situation

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Ben W

Probationary Member
25
2
Mar 7, 2017
Camp Lejeune, North_Carolina
Hey there folks, so im in a bit of a bind right now, as my car is in desperate need of a tune, yet nobody can seem to actually access my ECU
Here is what I know

The car had a NEW factory ECU installed, and as far as im aware, no aftermarket tune was done to it
The car seemed to drive fine as it was
(The car was NOT stock, like at all LOL)

That was 6 years ago
Having replaced the fuel injectors, and about to replace the turbo, (all the same size, just replacing worn/burnt parts) I've tried to get someone to tune the car after the fuel injector replacement (as a P0170 fuel trim code came up)
The tuner I got ahold of tried DSM link 3.0 and 2.0, as well as a few other programs, none of them recognized my ECU

So for the time being, i said screw it
AFR were in reasonable ranges (14.7 cruising, and they dropped for when I was under boost)
NOW, im about to replace a pretty worn out Turbo, and think i REALLY need to get it tuned afterwards
ALSO, the engine code will block me from passing emissions, which means I cant renew my registration

What can I do to "break into" my ECU so that tuners can actually tune the vehicle

Thanks for any advice!
 
You don't break into an ecu. You have someone modify it so that it can be tuned ala an ecmlink chip. Are you saying someone tried to flat-out hook up a laptop with ecmlink to your stock ecu? If it's stock then it can't be altered in that manner.
 
In order to tune with DSMLink, the ECU requires a special chip from ECMTuning in the EPROM slot, replacing the factory EPROM chip, or conversion work done to allow for their chip.

Looking back at your old posts, you have a 99 GST? This has an ECU that is incompatible with DSMLink. It uses a "flashable" type of ECU and would require some work like detailed here: First Flashed DSM ECU! (98/99 Flashing FAQ)
 
As 19Eclipse90 has said your ecu is the flashable "H8" ECU which is a little different than the older ECUs that were compatible with dsmlink. Now don't let that deter you in any way because with a little time and effort you can learn to tune it yourself. It does seem a little daunting at first, it was for me, but there is documentation of how to do it all.

The link that was posted it a good one to get started with but what helped me the most was the site that Ceddy has and keeps working even though he doesn't come around anymore.
this one http://ceddy.us/tuning/ has a list of the basic things you'll need to get started. A couple of notes from someone who has just went through this is

1. Just get the OpenPort 2.0 cable and don't worry about the VAG 409.1 cable not all of them work and will just frustrate you more.
2. make sure you have a wideband or you'll just be chasing your tail.
3. Logging wideband can be a pain. I opted for the the AEM uego wideband and used the serial to usb adapter to log while this isn't the best way I found it the easiest.
4. Evoscan 2.9 works just fine and as far as I know you don't need to add the Ceddymods file to evoscan, it has it built in.
5. If you have made it this far then you are ready to connect your laptop to your ecu, the first thing they tell you is to save your rom just in case. There might be an error message along the lines of no definitions and that as far as I know is normal just hit ok or accept.
6. If you are like me and don't have access to the real Microsoft Excel you can just use google sheets and import the data and end up with something like
You must be logged in to view this image or video.

I recommend formatting your data with the Format->number->0.00(near the bottom) that way when you make graphs they will graph the same.

Once you get the hang of it you'll have the graphs that will let you know that you need to rewire your fuel pump and possibly rescale your injectors like mine.
You must be logged in to view this image or video.


Before long you will get the hang if it even if you just don't go all out and fine tune every cell in the timing and fuel maps, you should be able to get it running real well
I hope this all helps and like I said don't let it overwhelm you, I just started learning a couple of weeks ago and have got this far.
 
Hey there folks, so im in a bit of a bind right now, as my car is in desperate need of a tune, yet nobody can seem to actually access my ECU
Here is what I know

The car had a NEW factory ECU installed, and as far as im aware, no aftermarket tune was done to it
The car seemed to drive fine as it was
(The car was NOT stock, like at all LOL)

That was 6 years ago
Having replaced the fuel injectors, and about to replace the turbo, (all the same size, just replacing worn/burnt parts) I've tried to get someone to tune the car after the fuel injector replacement (as a P0170 fuel trim code came up)
The tuner I got ahold of tried DSM link 3.0 and 2.0, as well as a few other programs, none of them recognized my ECU

So for the time being, i said screw it
AFR were in reasonable ranges (14.7 cruising, and they dropped for when I was under boost)
NOW, im about to replace a pretty worn out Turbo, and think i REALLY need to get it tuned afterwards
ALSO, the engine code will block me from passing emissions, which means I cant renew my registration

What can I do to "break into" my ECU so that tuners can actually tune the vehicle

Thanks for any advice!
Several posters have suggested you have a stock ECU but you need to verify which one. Since it has been replaced you don't necessaryily know what it has unless you look. Physically get it out of the car and look at it. Report back.
 
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