Projects: Truck EFI

underhood After graduating from college my daily driver was still my old 82 F100, and it was starting to get a little long in the tooth. The ignition was getting flaky and the carbeuretor was starting to give me problems with icing up in cold weather and going super lean in hot conditions as well as terrible dieseling, so I decided it was time to upgrade.

unassembled efi The first thing I did was buy a Megasquirt II to handle control since it was the cheapest and easiest standalone ECU by a wide margin, especially since I'm handy with a soldering iron, I was able to save even more by putting it together myself.

assembed efi With the ECU built it was time to start hunting down hardware. To keep it simple again I went with a Bosch 044 type fuel pump and the standard intake, fuel injectors and throttle body from a later model Ford inline 6 cylinder. Thankfully this let me get everything done pretty quickly. The whole conversion was done at my parents house over a weekend since I didn't yet have a place I could work on a car overnight.

HEI Sometimes when I was on the highway home the engine would just die on me. I was eventually able to track the issue down to a loss of spark as the problem got worse. At first it would just die for a second then come right back to life as if nothing happened. Eventually I'd have to pull over, let it sit for a minute or two then it would start again no problems. The Ford electronic ignition module is kind of complicated and unfortunately expensive to replace. Thankfully it does roughly the same thing as GM's HEI system which has been very popular in the after market scene for a while. I was able to pick up a basic 4 pin HEI module for about 20 bucks, connected up to the stock Ford distributor pickup and GM E-coil, and all was good again.


Post Mortem

Thankfully my truck still lives so this isn't quite a post mortem. I've had the truck running on this system for almost 5 years now and there's been a few hickups. Time hasn't been kind to the connectors I used. Including the fuse panel nothing was designed to be water resistant, and a lot of it is now suffering from corrosion issues and funky connections, I'll need to redo a lot of the wiring soon. Secondly I never got an O2 sensor with good readings on it so its never been well tuned. It's better than the old carb, but that's not really saying much. I had the system plugged into my laptop on the way home on the highway one day trying to use its built in auto-tune. This did not work. When I stopped for gas slow speeds in the city had it bucking terribly, and then it wouldn't start up again after fueling. To get home I put back on a super simple base map built sitting at the gas station, and its been running on that tune ever since. I also never really finished. I didn't come up with a fuel pump mount before heading out to my parents' for the epic weekend. I used a heavy duty zip tie to hold the fuel pump in so that I could get home and make something better. The metal for the new holder is still sitting in the shop, and the fuel pump is still zip-tied in place. I'll fix it one day I'm sure.