how to disable flex fuel?

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Imlow78

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Thanks a lot for the info. So is that calibration # something I could take to a dealer and the should know what Im talking about upgrading? I checked the Tech II owner list post but didnt see anyone near me in NC with one. Will also look into the cost of one of the custom tunes and whats involved with loading that on my ride. I got some gas today and now Im showing 63% alcohol lol
I just gave $389 for the Hp tuner module and one credit to work with the stock ecu on my 05 z71. Hope that helps.

Shannon
 

Fless

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I just gave $389 for the Hp tuner module and one credit to work with the stock ecu on my 05 z71. Hope that helps.

Shannon

I don't think HP Tuners can update the GM calibrations. You might be able to adjust some things but you'd want to know what you're doing.
 

Imlow78

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I thought he was wanting to remove the flex fuel stuff to try and get it to run correctly. I thought I read where that tuner could. Sorry guys.

Shannon
 

randeez

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i dont think an 05 has a virtual sensor, should still be the old style type sensor by the fuel tank, it is expensive but probably about the same price as a tune @$400 bux. if you want a tune anyway, then go that route and detele it. when they fail, its displays higher ethanol content i guess gm figured it would be better to run engine rich, than lean if it happens.

i dont see how a virtual sensor would "fail" all it does is assign an ethanol percentage to how far/fast the fuel trims change. you would have a leak after the maf sensor causing it to think the afr is rising(going lean) and needs more fuel to bring it back down to the commanded afr.

from rock auto it looks like this:
NTKFA0003__ra_p.jpg
 

Scottydoggs

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I just gave $389 for the Hp tuner module and one credit to work with the stock ecu on my 05 z71. Hope that helps.

Shannon

i just double checked my tahoe tune, its a 05 lt, hit engine then fuel tab, then the flex fuel tab, then you'll see a button for flex fuel and a drop down, set it to disable. then go to engine diag and then the DTC tab and find the codes for the flex fuel and set them to no report. all the codes have their description listed so most anything thats says flex fuel, set to "no error reported".

first things first tho, read and save the tune, name it stock what ever your truck is. with a do not touch, cause you never want to edit the original so you can always go back to it, or compare it to a edited file.

once saved open it up again then make your changes and go to file and save as, name it flex deleted or what ever comes to mind, and flash that file to the truck. i make a desktop folder for each car i tune and save the stock and all edited files in that folder. make slife easy when your looking for your files.

you'll also want to pull the radio fuse from under the hood fuse box and uncheck the high speed writing box in the flash window. leave the drop down box set to write calibration. never do a full write, unless you have to in order for some os segment swap stuff that your hopefully never going to need to do.

being my tune is open. its codes p0177 through p0183 delete all of them. my truck is non flex so those codes are already set to no report on my file. so you for sure dont want them active.

and pretty sure you need two credits to unlock your trucks pcm. what mine cost me. i did buy all my credits some time ago, they may have changed the sales with the newest mpvi2.

you'll also need to set up an account on the hptuners web site/forum. you need to sync the interface up to the web site to turn it on and make it yours. the directions in the box are pretty simple to follow, all that info is in there for ya. happy tuning :cool:
 

TollKeeper

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Or if you can live without the truck for a short time, you could pull the ECM, send it to @limequat.. I know he does the GMT360, I cant see that it would be much more of a tune for the NBS/NNBS

Have heard really good things about him..
 
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slowride

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Chevy dealer here in Greensboro quoted me $375 to update the calibrations. Not happening.
 

Scottydoggs

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Chevy dealer here in Greensboro quoted me $375 to update the calibrations. Not happening.

i would buy a hptuners and own it. it can be used on many cars. the scanner works on just about any car.
 

Fless

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Chevy dealer here in Greensboro quoted me $375 to update the calibrations. Not happening.

Independent shops can do the calibrations, too. Check around. Really, it would be best to have them read by a Tech 2, just to see what calibrations are in it.
 

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