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So we are converting my 02 Camaro over to flex fuel. So far we have the flex fuel sensor wired into pin 56 on the blue connector and are using a flex fuel OS from a 2002 Tahoe (OS 12216125) in which we changed the displacement from 5.3 to 5.7. We have upgraded the pumps and swapped out the fuel injectors to 1000cc FICs in preparation for boost. However, we are trying to get it running straight NA first. We know that the system is seeing ethanol content as we have been logging it already. We are using EFI Live for the tuning duties.
However, we are running to a few problems. First of all, the injector data that we input to EFI Live for the FICs keeps changing 2-3% after we save the file and reopen it. See the pictures below. This is after we put a base tune in it. The car starts but still isn't running right and there are other problems (see below)
Data just after inpute
Data after save and reopen
Data after input
Data after save and reopen
The second is that the BCM doesn't seem to be in communication with the ECM any longer. The 6-speed manual won't let us shift it into reverse after uploading the new OS and we have a constant "Service Vehicle" light on that wasn't there before. We updated the VIN on the new OS to match the car, but no luck.
Sorry for the long message, but I was hoping someone could point me in the right direction.
So it looks like I already answered one of my questions. I guess OS 12216125 isn't capable of being used with a manual transmission since it never came with that option. Thus, I can't segment swap it. Does anyone know of a flex fuel OS that originally came with a manual trans?
What is the code that the SES light is on for? Even though there may not be a manual for that OS, you might be able to do some manipulating to get it to turn off. These would be hex changes, but could be something to try.
The SES light isn't on at all. It's the "Service Vehicle" light--two different lights. I'm told the Service Vehicle light means that the computer is most likely not communicating with the BCM correctly, but I could be wrong. All I know is that now that we are running OS 12216125 in place of the stock OS 12212156 (in an attempt to run the car with flex fuel capabilities) it will no longer shift into reverse. I've heard that the OS 12216125 might not have the right communication protocols for the system period and won't work with the system.
One other thing that I have noticed is that the 12216125 OS was used in other trucks (e.g. Silverado's). Not sure if there is a magic truck OS which had a manual which you could try and segment swap to. As you indicated, it might not have been a valid combination from the factory. I know when I looked, I wasn't seeing one. Maybe somebody on PT might know if there is such an animal.
My guess on the reverse lockout is that the OS doesn't know it's a manual transmission. You can either try to fake the OS so that it's a manual (will require making some hex changes), or disconnect that lockout solenoid. The car will not longer be able to protect against shifting into reverse, but you will at least have reverse.
As for the service vehicle light, I am not as familiar with that one. I would have to do some looking to see if it's just the BCM that is unhappy, or if there was something else going on. Do the gauges in the dashboard still work?
Hmm deactivating the DTCs in an interesting idea. Maybe I'll have to play with this some more. I don't mind disconnecting the reverse lockout, I just don't want the service vehicle light on constantly. Though, I suppose I could pull the bulb for it. Yes, the gauges all work and the car drives just fine as long as I never have to use reverse. I didn't try any of the accessories like cruise control, traction control, or A/C though either.
I'll have to look into the '04 Corvette OS too to see if I can get something like that to work. I'll test these out and let you guys know. Hopefully I can get it to work and we'd have an easy solution for getting fourth-gens going flex fuel.
Betting the A/C won't work, since the Tahoe's had a different A/C system. This is a known issue and can be fixed by switching the A/C Type. I've mapped it out in several OS's if your interested.
As for the '04, yes there are several Flexfuel OS's in the 1 MB PCM's. If you not stuck on a 512 kB, then going to a 1 MB would be an easier swap IMO.
Betting the A/C won't work, since the Tahoe's had a different A/C system. This is a known issue and can be fixed by switching the A/C Type. I've mapped it out in several OS's if your interested.
As for the '04, yes there are several Flexfuel OS's in the 1 MB PCM's. If you not stuck on a 512 kB, then going to a 1 MB would be an easier swap IMO.
Which OS would you recommend for an 04 GTO with a manual transmission?
I did a quick look at the 2004 GTO OS (should be 12587604). It looks like the flex fuel tables are in there, just not turned on. You should be able to use this OS, but you will have to populate the flex fuel tables (mixture, spark, etc...). The other 1 MB OS's that I mentioned had flex fuel from the factory (tables already filled in). But they are a different OS and would not segment swap nicely with what you already have.
So far I have a P59 pcm and trying to use an 2005 chevy avalanche file. But I am being told this can't be done using EFI Live? Are you guys all using HP Tuners?
Why can't you do it in EFI Live? If you start with a flex fuel OS, then it's very easy. Even if you don't have a flex fuel OS, EFI Live has the tables to modify.
Why can't you do it in EFI Live? If you start with a flex fuel OS, then it's very easy. Even if you don't have a flex fuel OS, EFI Live has the tables to modify.
I'm not exactly sure which OS a 2005 Avalanche is, but if it is 12592618, then EFI Live does have a COS 3 (which supports 3 bar) for it. The good news, is that the 2003-2005 OS's are very interchangable and you could just use a 2004 OS (Avalanche or other vehicle). There are more COS's for 2004 than 2005.
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Flex Fuel Fourth-Gen 
