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View Full Version : Wanted: E39 Flexible Fuel Tunes



engimuneer
April 30th, 2012, 06:35 AM
Doesn't matter what vehicle (but prefer 2012 Traverse). Trying to compare what GM uses for its stock FFV settings to those without. My email is my screenname at gmail.

GMPX
April 30th, 2012, 10:19 AM
I don't have a 2012 Traverse tune, something important though, the vehicles I've seen with FlexFuel enabled using an E39 also have a real ethanol sensor, they don't use the estimation system any more. So I suspect the estimation calibrations may not be complete enough to make it work if you just tell it the vehicle is FlexFuel enabled, you might need to fit a real sensor to the car.

engimuneer
April 30th, 2012, 10:23 AM
Thanks for the information. Exactly what we're trying to find out with this ECM & tests. The 'default' setting is FF off & calculated sensor. I'm actually surprised with how many fields they do have filled in for E85. Most of the time they seem to be left blank. I'll know by Wednesday whether it worked or not. Awaiting a 2012 Impala 3.9L FFV ECM to swap in place of the 12 Traverse. Didn't realize they were already reimplementing the actual sensor in 2012. Thought they were waiting for 2013 models & the EPA Tier III standards.

GMPX
April 30th, 2012, 10:30 AM
Awaiting a 2012 Impala 3.9L FFV ECM to swap in place of the 12 Traverse.
Do you mean 3.6L? SIDI is only on the 3.0L and 3.6L.


Didn't realize they were already reimplementing the actual sensor in 2012. Thought they were waiting for 2013 models & the EPA Tier III standards.
Thinking about it, all our local 2012 cars here in Australia (both V6 and V8's) so E38 & E39 ECM's have all gone to a real sensor too.
Perhaps they couldn't get the accuracy with the estimation system or it was taking up too much CPU power to do it, only GM would have the answer there. Whatever it was it must have been a no win situation because think of the cost of installing a sensor on every car now. At least as a spare part (assume a 300% mark up) they are super expensive.

It's hard to know just what platforms had the FlexFuel parameters all done in the background. The only one I know that never had any FlexFuel cals set was the Northstar V8 on the E67, the give away is the Stoich table, if that all all the same then you are out of luck.

engimuneer
May 9th, 2012, 03:14 AM
I did mean the 3.6L SIDI, which felt like an awesome engine! We got 26.5 MPG with the Traverse at over 6000 feet. Unfortunately many of the PIDs were not working (SAE.E85R, E39AF_DEM, GME85PCT, etc...), we did find the vehicle got 22 MPG with E85 and its LTFT were only around 4%. That indicated to me the vehicle was flex fuel capable with a simple reflash. Most of the 8 ethanol tables were populated (E37 has 21) and I only had to put in a few scalars. Same basic story with an 11 Malibu 2.4L, sold to fleets FFV, not to citizens.

I'm told GM went away from the virtual sensor due to the new EPA Tier III emission and OBD standards. The algorithm just isn't accurate enough for the EPA (we've had several refill's mislearn the fuel type, decreasing gas mileage and raising emissions). Shame, because that extra $100 sensor might have lost the FFV war.

Wish I could get into the files and see these algorithms in action. I've found all 07+ GM vehicles have some FFV capability, but like you've said, the level of calibration might be off for many of those.

GMPX
May 9th, 2012, 11:15 AM
I'm told GM went away from the virtual sensor due to the new EPA Tier III emission and OBD standards. The algorithm just isn't accurate enough for the EPA (we've had several refill's mislearn the fuel type, decreasing gas mileage and raising emissions). Shame, because that extra $100 sensor might have lost the FFV war.
I believe the new E85 sensor is not the one from early 2000, so maybe it's a bit cheaper? I don't have a part number to check though. I have a vehicle with an LFW outside but I have no idea where they mount the sensor (don't anyone be smart and say in the glove box!).

engimuneer
May 15th, 2012, 09:11 AM
Did you want the 2012 Traverse & Impala tunes emailed to you? Like I mentioned, the Traverse behaved great as an FFV with the virtual sensor enabled.

GMPX
May 15th, 2012, 10:10 AM
The new sensors are only $66!!

Dieselman
May 15th, 2012, 11:13 PM
The new sensors are only $66!!

Is that the price for the Ethanol sensor??

I think the sensors are mounted on the fuel tank in the Holden VE.

Ben

Dieselman
May 15th, 2012, 11:24 PM
Fuel composition sensor on Holden VE tank. Sensor on LHS I think :mrgreen:

13166

GMPX
May 15th, 2012, 11:57 PM
That is the one, $66 from GM Parts Direct, I hear around $170 from Holden :bad:
What is the part number on that one? Also, can you tell what size fuel lines that one uses?

Dieselman
May 16th, 2012, 12:20 AM
That is the one, $66 from GM Parts Direct, I hear around $170 from Holden :bad:
What is the part number on that one? Also, can you tell what size fuel lines that one uses?

I got the photo off someone else on the EFI Melb facebook group. Maybe Simon or Luis could get a part number from a newer car. My car is a 08 Calais and does not run a sensor but I was hoping to retrofit one to it for running E85 in the future

Cheers

Ben

GMPX
May 16th, 2012, 12:38 AM
Well, in the past the sensor has been so expensive it wasn't really attractive.
Of course you'd still need to get the fuel line fittings, electrical connectors etc, it might all add up a bit, still, I wouldn't hesitate to do it.

engimuneer
May 16th, 2012, 03:30 AM
Best news I've heard all week. I'll order one this week!

Just got off phone with GM
PN 13577379

2012 Impala was what I used for the part search.

GMPX
May 16th, 2012, 09:53 AM
There is another, 13577394, this is the one on the V8's.
I suspect the difference will be the size of the fuel lines in-out of the sensor, but I don't know for sure.