I just finished modding my car to run off of e85, yes I said e85 (although right not i have half a tank of gasoline and half a tank of E85, i plan to full it up fully with e85 on my next fill-up)
I purchased a FFI Platinum E85 Ethanol Conversion Kit (sold on changetoE85.com, I managed to find a 6 cylinder version on ebay for dirt cheap, works great despite only having 4 cylinders) Installation is easy and while I just installed and have only driven a little bit with the kit, the car appears to run quite well. no misses or lack of performance. anyway, here is my how-to:
here is a picture of my installation:
I mounted it on top of the fuse box with velcro, will make it easy to remove if i ever need access to the fuse box. and there is a great place to ground the unit nearby, as shown below:
Next, I had to connect the unit to the fuel injectors. it intercepts commands from the car's computer and sends different commands to the fuel injectors, thus changing the injector valve timings in order to pump more e85 into the engine. otherwise your car would likely stall as e85 is not as powerful as gasoline, but it is cheaper, burns cleaner and cooler, and is rated at 105 octane (just to clearify, octane rating refers to the likelyhood of autoignition of the fuel and not the amount of octanes in the fuel, this is a popular misconception, basically, the higher the octane rating, the less likely you will have fuel prematurely igniting, thus your engine will run more smoothly off of e85). my kit was a 6 cylinder version because i got it for cheap. so two of my conectors aren't used, I zip tied those off. for those wondering, my car uses ev6 connectors to the fuel injectors. I am willing to bet that most other cobalts use the same connector, in case you want to make sure this guide will show you how to get to the connectors to see. to get to the fuel injectors you have to remove an assembly which connects from the air intake manifold to the airbox. (yes, they made this install a pita on the cobalt, most other cars this install is super easy on). the screws you need to loosen to remove this assembly are shown below:
once you have removed the plastic parts over the engine you should have access to the fuel injectors (they are under the fuel rail, and a pita to get to) just connect the kit into the injectors, and the connectors coming from the computer into the male connectors on the kit, reassemble everything and you are good to go (make sure the wired are away from the fuel rail and anything else that would burn the wires, I used zip ties to accomplish this.) after everything is assembled start the car, make sure no check engine light comes on. and you are ready to start using e85 (the directions for my kit recommend after installation filling up with half gasoline and half e85, then the next tank going full e85, then you can do any mixture you prefer)
it is also recommended that you do an oil change and replace your fuel filter after 1000 miles of running off of e85.
the kit also came with an e85 flexfuel badge, I put it on the trunk lid:
I HIGHLY recommend making sure that you have gas stations that sell e85 nearby where you live, you can do that at Growth Energy Market Development
. installing this kit would be pointless if you didn't have them nearby
. you may lose up to 20% mpg on your vehicle due to the injecting of more fuel into the engine, but with e85 prices hovering around $2.30 per gallon, the fact that e85 is made in america, and it is cleaner both for your engine and the environment. I will be sure to post further news about my latest modification, as well as my mpg now, so that we can see if it is truely worth the 150-300 dollars that e85 conversion kits are.