Hey guys. I remember reading somewhere that not all P59 PCM's are flex fuel ready because they have different operating systems. See the attached base file
Thank you
2005 Siverado 6L swap Scott Base.hpt
Hey guys. I remember reading somewhere that not all P59 PCM's are flex fuel ready because they have different operating systems. See the attached base file
Thank you
2005 Siverado 6L swap Scott Base.hpt
ANY P59 OS can be Flex Fuel. My L31 based 383 has a non flex fuel calibration running with factory flex fuel.
The only P01 and P59 vehicles I tune with HPTuners were ones I already had licensed. For swap stuff now, I mostly use a P59 12592618 OS on swap vehicles. I have files to literally run nearly anything with that OS.
Get a $50 OBDLinkSX cable, download PCMHammer, download Universal Patcher. Read the PCM, Modify the .BIN file with the Flex Fuel Patch, Write the File and done.
Last edited by Fast4.7; 01-09-2023 at 01:33 PM.
I have a stock 2003 Sierra 5.3 non Flex fuel, how would I know if the stock OS can run flex fuel? I just ordered the Hp tuner so I can attempt to do this but just saw your post saying OBDLinkSx cable would work also, I don?t plant on doing anymore tuning than necessary to make mine flex fuel would the OBSLinkSX be enough for that?
I?ve got all day doing research I just realized once I posted you already said any P59 can be, does that mean that some P59 aren?t but can be made to be, or that they all come with the option to run the flex fuel sensor?
They all have the option to run a FF sensor, but HPT has not defined some tables to get it working. You can edit these missing tables via "User Defined Parameters" with and XDF that identifies these parameters. What OS do you have? I may have an XDF I could share for the FF stuff.
I found a 03 Silverado FF truck calibration that uses the same OS that the non FF trucks use. So perhaps that OS will enable FF with just the switch. Typically they don't. What I would do though is segment swap the Engine and Engine Diag segments into your calibration bcause those are different so all the FF tables will be populated correctly. This is assuming your truck uses OS 12579405. Right now I only have it in Tunercat file format but I can load it in a PCM and read it back out with HP Tuners if you need it.
Ahh that makes more sense. I could turn fFF on but would have to manually define the tables tgat I would need. I think it opens up a lot of room for user error to do it manually unless it could be copied and pasted on to mine.
I?m unsure of how to check what OS I have. I figured that?s something I would have to check with the tuner but I haven?t received it yet. Is there another way of checking?
There is a chance your main OS number will be the same as the FF calibration I have (12579405). If it is then you would put the engine and engine diag segments from the FF file I have into yours. HP Tuners software will let you do that if both files have the same main OS #. Trucks that came with FF are kind of rare. They are more abundant in Tahoes, Yukons, and Suburbans. You will have to read your PCM first to see what OS your truck has in it.
Last edited by 2xLS1; 02-27-2023 at 01:08 PM.
First of all, Thanks a ton for all the help! I was doubting if I should go through with this thinking I?d have a hard time getting any help if I ran into any problem and here you are helping and I haven?t even ran into any problem yet ;D
I will wait for the tuner to get here then so I have a better idea of what I?m going to have to do. If I have a different OS I?m assuming I?ll have to change the entire OS, and from what I have read that includes having to change the vin correct?
Don't confuse changing the VIN with changing the OS. You might not have to do either. Wait until you have read your PCM until you worry about anything else.
In the process of reading my PCM
I have OSID 12579405
I found the bin for a flex fuel but it?s a rwd model on the following page
https://pcmhacking.net/forums/viewto...=6208&start=20
Not sure if that would work or if I would need to find a 4x4 for what I am looking for since mine is 4x4
Segment swap the engine and engine diag segments from this file into your file. It is 4x4.