I'm putting together a hardware package to show the ethanol percentage in the Fiesta ST. This will be handy for people that use Ethanol in their FiST to know EXACTLY what you have in the tank. Coupled with the new COBB map switching this will be a great feature. You will be able to run a custom rom that has Ethanol percentages in each switchable map slot to switch to and you know which one to switch to based on what the gauge is telling you. No more math at fill up and no more guessing when you add Ethanol to a non-empty tank. My dream is to that the ECU will switch to each map automatically depending on the Ethanol percentage in your tank but that will take COBB getting on board with it and the output of the sensor wired to the ECU. I will be outlining the EXACT parts you need to purchase in list form and a how-to assemble them and wire everything up. I will share this freely in the spirit of information and collaboration. 12-23-2014 UPDATE Since some DB on the other forum (gee I wonder who) decided to copy all my and ideas and info and start his own thread (since they deleted all my tech info) about it I am updating this and the first post in this thread with all the required items to get this working. I'm currently testing this all out and with the COBB switchable maps, it's going to be a great combo. Parts list: 1. Continental VDO Flex fuel sensor. GM Part # 13577429, approx $55 I went with the smallest sensor they make for space reasons. 2. Russell 644123 -6AN Male to 3/8" SAE Fitting (2) $17/each @ Amazon These are the quick connect fittings to the sensor. You can go cheaper with the plastic connect versions but there have been reports of the plastic breaking down with E85 so these are much safer and more robust. Cheaper version: Dorman 800-082 STRAIGHT. 3/8 IN. STEEL TO 3/8 IN. NYLON (pack of 2) 3. Russell 644113 -6AN Male to 5/16" SAE Fitting (2) $21/each @ Amazon This connects to the OEM fuel pipe to the HPFP pump on top of the motor and the other to the OEM Fuel line at the firewall. Cheaper version: Dorman 800-092 90 DEGREE ANGLE. 5/16IN STEEL TO 3/8IN NYLON (pack of 2) Dorman 800-084 STRAIGHT. 5/16 IN. STEEL TO 3/8 IN. NYLON (pack of 2) 4. Radium PTFE -6AN Hose Assemblies - 11.4" Straight and 90* ends (2) $22.95/each @ Radium PTFE for great ethanol resistance and -6AN connections for secure and non-leak fit. Pre assembled. Cheaper Version: Any 30R9 spec hose, Gates, Goodyear etc. Two feet. Fuel injection hose clamps 5. Zeitronix ECA Ethanol Content gauge $199 6. Zeitronix ECA 8ft wiring harness $29 You can find this harness cheaper to build yourself but this is well done and saves time If you want to make the Sensor wire harness yourself, here are the part #'s for the connector: Delphi GT 150 series connector, part # 13519047 (1) $1.62 Delphi GT 150 series Terminals part# 15326264 (3) $0.10 each Delphi Loose Cable Seal part# 15366021 (3) $0.06 each Or buy the GM connector harness already assembled and cut one end off GM Part# 13352241 $9.71 EFI Connection also sells a pre assembled connector pigtail for $15.00 http://www.eficonnection.com/eficonnection/ItemDetails.aspx?ItemId=1222 7. Add-A-Fuse $9 @ Amazon or local auto store The two pre built Radium PTFE hoses and the Zeitronix ECA wiring harness makes this a basically plug and play affair. I highly recommend going this route to save time but of course you can build it all yourself if you want. Wiring instructions Orange wire : +12V (use Add-A-Fuse connection makes this a plug and play affair to the fuse box) Brown: Ground (use one of the many grounds located behind the glove box or foot well areas Green: Sensor output to Zeitronix ECA gauge Fueling connections The OEM hard line is located at the top right of the engine if you are looking at the windshield of the car. BE SURE TO RELEASE FUEL PRESSURE BY PULLING THE FI FUSE IN THE FUSE BOX AND CRANKING THE CAR BEFORE DOING ANY OF THIS. Undo the L-shaped connection with the two black prongs below: Follow this line down towards the firewall and undo the other side the same way you did the engine side of the hose. Install the Russell 644113 -6AN Male to 5/16" SAE Fitting on the OEM hard line at the top of the engine. Be sure to lube the o-ring in the connector first. Once you install this fitting onto the OEM hardline, install one of the Radium PTFE -6AN Hose Assemblies on this side, install the Continental VDO Flex fuel sensor on the end of this with the two Russell 644113 -6AN Male to 5/16" SAE Fitting fittings on it, then install the second Radium hose on the other end of this. Install the second Russell 644113 -6AN Male to 5/16" SAE Fitting on the OEM hard line at the firewall and then install the last open end of the second Radium hose. This completes the whole assembly. As you are assembly all this you will see the proper way to orientate everything in the engine bay. It's really simple. I used black zip ties to make sure some of the hoses where secure and wouldn't flop around the engine bay. Then connect the zeitronix wire harness to the sensor and find the way you want to bring it into the cabin depending on where you want the gauge placed. Wire everything up and there you go!