Joined
·
340 Posts
I'm writing this to try and help some folks out. The information surrounding this seems vague at best and searching often results in threads that never answer the question, but turn into a whole other subject matter when folks start asking about engine setups.
This is about adding a Flex Fuel sensor to a 2004 GTO using the stock ECU that the car comes with. That's it.
Stuff you need:
1. A flex fuel sensor. There are a few to choose from. I used this: Delphi P/N 13577429 (genuine OEM Continental sensor) I bought it from here: https://www.racetronix.biz/product.asp?ic=13577429
2. You'll need at least one of those little bitty pins that go inside the harness. I found a place that sells them; EFI Connection in Erie, PA. The other option is run down to a junk yard and buy a segment of the harness going to the ECU for any 2004/2005 GM car/suv. Snip it off a few feet from the plug. Then you just get the pin out of the plug and pull the entire wire with pin attached. Either way, pretty easy to do and cheap.
3. Flex fuel sensors are stupid simple in how they function. All it does is look at the color of the fuel. Colorless means more ethanol. Darker means more gasoline. That's it. The sensors have 3 wires. White=signal that you run to your ECU. Red=switched 12v power. Black=chassis ground.
If you are electrical idiot guy (like me) switched 12V power just means that you wire this into something that only has power when the key is in the ignition and you've switched it to "on". Running this sensor to a non switched 12V source would work fine, but it will cause a drain on the battery.
4. On 2004 GTO's the ECU lives under the big coolant tank on the D Side. You'll have to remove that tank. If your a bad ass you can move it without slopping coolant everywhere. I am not a bad ass so I drained it first. That kinda sucks as getting the coolant system air free is a little work, but whatever. Once the tank is pulled you wrestle with the black plastic cover that acts like an umbrella on the ECU. Get that off and you see two plugs retained by a single 7mm hex head screw. Ok, you are now ready to remove one of those.
Important: STOP and DISCONNECT your battery cables from your battery. ONCE and ONLY AFTER you have REMOVED BOTH battery cables, touch the two cables together. Again. ONLY after you have removed them from the battery! The reason for this is to kill any static or residual current that might be lingering somewhere. It's probably not even needed, but I am a bit paranoid when working with anything ECU related. Just like a computer at home, static can make a mess of things.
Ok, remove the 7mm screw from the harness on the INBOARD side of the ECU. Once removed it will have a blue color on the plug. The plug has a funky plastic cover/shroud that is clipped on each end and in the middle. As with any wiring things, its kind of a PITA to remove. Patience works here. Just pinch and tug. It will come off. It will likely have a single zip tie holding it to the harness. You do not need to cut the zip tie.
5. Now build or get your wire. Give yourself 3 or so feet of total length. Inspect the back side of the plug. Those pins are numbered. #56 is the one you want for the 2004 GTO. Inspection will show it has a rubber thingy in the hole. Just poke it with a pick. It'll perforate and that'll allow you to shove your pin in. Carefully install the pin from the back side. You'll need to push fairly hard to get it fully seated. You can hear a very faint click once it seats. Attempting to remove it by tugging the wire will confirm if you have it right or not.
That's it. Now reinstall the plug and put stuff back where it goes opposite of how you started. Leave the battery alone for now.
6. Run your wire to the white wire on the sensor. That is signal. The other two as previously covered are power/ground.
7. Plumb your fuel line to the sensor. I did mine on the return. I leave that decision to you. There's really no right/wrong answer here from what I can tell.
8. Now, using this thing:
The 2004 computer will support this upgrade. What will NOT work is the operating system currently installed in your car. For the illiterates this basically means that if you like using Cortana in Windows to look for stuff, you had to change the windows operating system to something like 10 or newer for you to use it in your PC right? The old days of using Window's XP just has no way of supporting it.
It's the same thing here sorta. We have to find a vehicle with an operating system that already has flex fuel capability and is also compliant with the ECU found in the 2004 GTO. This is pretty easy. The HP Tuner website has an archive called the repository. The "Hall of Records" for all things holy and related to this stuff.
What your looking for is an OS for a 2004 GM Fleet Van or an Escalade. There is no advantage of one over the other.
This OS gets loaded into your car via HP Tuner Sofware. If using EFI Live with a custom OS you'll need to just set it up that way.
Then its basically a function of ensuring the parameters in the software turn everything on and your tables for fuel delivery and igntion timing are calibrated appropriately. Be it either you or a well vetted shop doing that work.
But that is basically it and put into layman terms. I know I loath researching stuff where everyone talks in 3 and 4 letter codes that I then have to look up and decipher. Hopefully this helps. If there is something I left out, add to it but PLEASE SPEAK PLAINLY.
The whole point of a forum is to provide a platform for sharing information, not showing how smart you are with vocabulary abbreviations.
EDIT:
Here is a thread related to the fittings the sensors use: https://www.ls1gto.com/forums/showthread.php?t=835522
Hope this helps.
C.
This is about adding a Flex Fuel sensor to a 2004 GTO using the stock ECU that the car comes with. That's it.
Stuff you need:
1. A flex fuel sensor. There are a few to choose from. I used this: Delphi P/N 13577429 (genuine OEM Continental sensor) I bought it from here: https://www.racetronix.biz/product.asp?ic=13577429
2. You'll need at least one of those little bitty pins that go inside the harness. I found a place that sells them; EFI Connection in Erie, PA. The other option is run down to a junk yard and buy a segment of the harness going to the ECU for any 2004/2005 GM car/suv. Snip it off a few feet from the plug. Then you just get the pin out of the plug and pull the entire wire with pin attached. Either way, pretty easy to do and cheap.
3. Flex fuel sensors are stupid simple in how they function. All it does is look at the color of the fuel. Colorless means more ethanol. Darker means more gasoline. That's it. The sensors have 3 wires. White=signal that you run to your ECU. Red=switched 12v power. Black=chassis ground.
If you are electrical idiot guy (like me) switched 12V power just means that you wire this into something that only has power when the key is in the ignition and you've switched it to "on". Running this sensor to a non switched 12V source would work fine, but it will cause a drain on the battery.
4. On 2004 GTO's the ECU lives under the big coolant tank on the D Side. You'll have to remove that tank. If your a bad ass you can move it without slopping coolant everywhere. I am not a bad ass so I drained it first. That kinda sucks as getting the coolant system air free is a little work, but whatever. Once the tank is pulled you wrestle with the black plastic cover that acts like an umbrella on the ECU. Get that off and you see two plugs retained by a single 7mm hex head screw. Ok, you are now ready to remove one of those.
Important: STOP and DISCONNECT your battery cables from your battery. ONCE and ONLY AFTER you have REMOVED BOTH battery cables, touch the two cables together. Again. ONLY after you have removed them from the battery! The reason for this is to kill any static or residual current that might be lingering somewhere. It's probably not even needed, but I am a bit paranoid when working with anything ECU related. Just like a computer at home, static can make a mess of things.
Ok, remove the 7mm screw from the harness on the INBOARD side of the ECU. Once removed it will have a blue color on the plug. The plug has a funky plastic cover/shroud that is clipped on each end and in the middle. As with any wiring things, its kind of a PITA to remove. Patience works here. Just pinch and tug. It will come off. It will likely have a single zip tie holding it to the harness. You do not need to cut the zip tie.
5. Now build or get your wire. Give yourself 3 or so feet of total length. Inspect the back side of the plug. Those pins are numbered. #56 is the one you want for the 2004 GTO. Inspection will show it has a rubber thingy in the hole. Just poke it with a pick. It'll perforate and that'll allow you to shove your pin in. Carefully install the pin from the back side. You'll need to push fairly hard to get it fully seated. You can hear a very faint click once it seats. Attempting to remove it by tugging the wire will confirm if you have it right or not.
That's it. Now reinstall the plug and put stuff back where it goes opposite of how you started. Leave the battery alone for now.
6. Run your wire to the white wire on the sensor. That is signal. The other two as previously covered are power/ground.
7. Plumb your fuel line to the sensor. I did mine on the return. I leave that decision to you. There's really no right/wrong answer here from what I can tell.
8. Now, using this thing:
The 2004 computer will support this upgrade. What will NOT work is the operating system currently installed in your car. For the illiterates this basically means that if you like using Cortana in Windows to look for stuff, you had to change the windows operating system to something like 10 or newer for you to use it in your PC right? The old days of using Window's XP just has no way of supporting it.
It's the same thing here sorta. We have to find a vehicle with an operating system that already has flex fuel capability and is also compliant with the ECU found in the 2004 GTO. This is pretty easy. The HP Tuner website has an archive called the repository. The "Hall of Records" for all things holy and related to this stuff.
What your looking for is an OS for a 2004 GM Fleet Van or an Escalade. There is no advantage of one over the other.
This OS gets loaded into your car via HP Tuner Sofware. If using EFI Live with a custom OS you'll need to just set it up that way.
Then its basically a function of ensuring the parameters in the software turn everything on and your tables for fuel delivery and igntion timing are calibrated appropriately. Be it either you or a well vetted shop doing that work.
But that is basically it and put into layman terms. I know I loath researching stuff where everyone talks in 3 and 4 letter codes that I then have to look up and decipher. Hopefully this helps. If there is something I left out, add to it but PLEASE SPEAK PLAINLY.
The whole point of a forum is to provide a platform for sharing information, not showing how smart you are with vocabulary abbreviations.
EDIT:
Here is a thread related to the fittings the sensors use: https://www.ls1gto.com/forums/showthread.php?t=835522
Hope this helps.
C.
