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View Full Version : E38-2011 Corvette Grand Sport full flash, get "service traction system" + "stability



Praxis
June 23rd, 2014, 07:26 PM
East Coast Supercharged Grand Sport Corvette, 2011. They supplied a base tune using a map sensor from a zr1. They said it needed a full flash, therefore selected "flash tune and operating system" in newest release of V7.5

Flashes, and on restart, cranks for a long time (presumably while MAF fails), and then gives error on the dash "service stability control system" Traction control system, and on first start, "Service electrical system". On restart, no electrical system error.

Here is the tun file they supplied. They told my friend they have lots of these running around, and this was the first with with this issue. After our first attempt they sent another file with same result.

If we flash it back to "stock" with just a few changes for 60# injectors, and re -install stock map sensor, it runs and drives with no errors.

Any suggestion?

Praxis
June 24th, 2014, 05:25 AM
Bump!

lol.

So tried just a normal flash, seems like exact same result.

Does the On Star fuse have to be pulled or something?

Is it not taking the full flash even though it says it is?

GMPX
June 24th, 2014, 08:43 AM
No known issues exist with E38 flashing and typically no fuses would need to be removed when flashing.
If the car runs ok with the slightly modified stock tune then it must be something in the supplied tune.

swingtan
June 24th, 2014, 09:01 AM
Agreed. There is no "MAF fail delay" when cranking, as the E38 runs in SD mode till the engine fires, so the MAF has little to do with air flow. In fact, if you run a MAF tune and unplug the MAF, the engine will fire then die when the ECM attempts to read the MAF.

The tune sounds off, but I can have a look at it later on.

Simon.

swingtan
June 24th, 2014, 01:36 PM
OK, had a look at the tune.

It's certainly a "starter" tune, as the VVE looks rather stock for a FI car. The rest seems OK, although B1832 is a bit interesting, it looks a bit high when the engine is warm and there's a funny spike at 20'C. It looks like a bad cut-paste.

For the long crank issue, is it only occurring first start after the re-flash or every cold start?

I can't see any reason it'd cause the warning lights though, have you confirmed the OS numbers between the original and this tune?

Simon.

Praxis
June 24th, 2014, 05:05 PM
OK, had a look at the tune.

It's certainly a "starter" tune, as the VVE looks rather stock for a FI car. The rest seems OK, although B1832 is a bit interesting, it looks a bit high when the engine is warm and there's a funny spike at 20'C. It looks like a bad cut-paste.

For the long crank issue, is it only occurring first start after the re-flash or every cold start?

I can't see any reason it'd cause the warning lights though, have you confirmed the OS numbers between the original and this tune?

Simon.

Thanks.

Long start only on first start. Then ok. At one point we tried disconnecting the battery to try clear the active handling and traction lights (the traction control light on dash is also on). After we did that, we could not re start the car no matter what we tried.

Re flashed it, and it started. Ditto clearing the pending codes with scan (maf high or whatever). Had to reflash to get it to start.

joecar
June 25th, 2014, 09:40 AM
Do you have a stock ZR1 file that we can compare against...?

Praxis
June 25th, 2014, 03:35 PM
Do you have a stock ZR1 file that we can compare against...?

I'm not sure if that is a zr1 tune file, or they just named it that because they put a zr1 map sensor in it. Grand Sport vette is just an ls3 afaik. The supercharger kit is a centrifugal style.

So, the car had headers, and a tune before, I'm attaching the tun file it drove in on. Buddy then changed the map sensor, and added 60# injectors, and I loaded the previous posted "zr1" tune file.

THanks for looking guys

DrkPhx
June 28th, 2014, 07:37 AM
You shouldn't have to full flash it. I've never seen this on an E38, but I have seen it on an E67 where the CAN Bus connection is not re-established between the ECM and BCM after a flash. The Service Stabilitrak message will normally display on the DIC during the start of the flash, but will reconnect after it's complete, then the normal DIC values will display. Pulling the BCM fuse will usually fix it. Try a normal flash (not full) with the provided tune. If the problem persists, then there probably is corrupt data in the file and should be discarded for a new one.

DrkPhx
June 28th, 2014, 07:41 AM
Try copying all of the data from the "tune" to the stock file, resaved it with a new name then flash it to see if that works.

Praxis
June 28th, 2014, 01:37 PM
Try copying all of the data from the "tune" to the stock file, resaved it with a new name then flash it to see if that works.

At one point I did just a regular flash, same result.

This is the second map they sent.

I dunno, at this point, it would probably be just as good to just tune from scratch. Looking at their injector values for the SD 60's, seem a little "chinsy" compared to what I have for them anyway. Doesn't seem like a lot of effort went into their tune.

Thanks for the help guys, appreciate it.

DrkPhx
June 28th, 2014, 11:16 PM
I agree it would be better to start from scratch at this point. Mail order tunes are rarely spot on from the start and forced induction makes it even tougher. Do you know how to use the compare feature? I ask because you can compare the tunes side by side which shows some interesting changes that may or may not be relevant. There are quite a few odd things in this tune mostly in the DTC area.

Can you confirm if the "base" tune you posted is the actual unmodified stock file? If not, can you post it?

Some observations
- The MAF values were modified, yet the MAF is set to fail if above 1hz and below 1126hz. The MAF DTC's are set to No MIL.
- There are several DTC's changed to "non-emissions" including U0073 "Control Module Communication Bus Off"
>I don't if they changed these; but I would compare them to the stock values to make sure.
- Some of the TCS options were turned on; yet the tip in torque values are maxed out.
> Once again compare these to stock to confirm. I would leave these stock.
- The injector Flow Rate slope is completely different between the two; yet both reference vacuum.
> Do you have the complete set of values for these injectors?

It's up to you I would consider asking for a refund and trying another tuner or building your own tune since you already have the software (or is it Autocal?)

Praxis
June 29th, 2014, 03:48 AM
I agree it would be better to start from scratch at this point. Mail order tunes are rarely spot on from the start and forced induction makes it even tougher. Do you know how to use the compare feature? I ask because you can compare the tunes side by side which shows some interesting changes that may or may not be relevant. There are quite a few odd things in this tune mostly in the DTC area.

Can you confirm if the "base" tune you posted is the actual unmodified stock file? If not, can you post it?

Some observations
- The MAF values were modified, yet the MAF is set to fail if above 1hz and below 1126hz. The MAF DTC's are set to No MIL.
- There are several DTC's changed to "non-emissions" including U0073 "Control Module Communication Bus Off"
>I don't if they changed these; but I would compare them to the stock values to make sure.
- Some of the TCS options were turned on; yet the tip in torque values are maxed out.
> Once again compare these to stock to confirm. I would leave these stock.
- The injector Flow Rate slope is completely different between the two; yet both reference vacuum.
> Do you have the complete set of values for these injectors?

It's up to you I would consider asking for a refund and trying another tuner or building your own tune since you already have the software (or is it Autocal?)

Thanks for the help. No, the "stock" calibration is not stock, and I do not have a stock one for the Grand Sport, assuming it's a bit different because I think it was rated at a little more power than an LS3. That is why I was hoping to use the supercharged supplied tune as a base.

I have some old Siemens Deka 60 values that I could use that SHOULD be close. I have not found anything "complete" for them online. If someone has a link so I can compare, that would be great.

The tune came as part of the kit, and they claim they have hundreds of cars running on it....

Praxis
July 1st, 2014, 01:38 PM
Try copying all of the data from the "tune" to the stock file, resaved it with a new name then flash it to see if that works.

Well... Did this. Car did the same. So, started undoing changes till it ran.
.

MAP sensor... Apparently, zr1 sounds like zl1 to a parts guy lol. So zl1 map sensor with zr1 tune values throws the traction control and stability systems into a frenzy lol.