DIY Fuel Injection for any Carbed Engine! HOW TO!

Well this thread may take awhile to finish but I thought some guys might find it useful and less intimidating if they knew some of the basics. I'll be working on it while I do this one and taking pictures along the way!

Disconnect battery because if you see smoke when removing one of these systems? You lost the magic! :mrgreen:

Like getting the parts you need. First try to find a donor vehicle with approximately same size engine as you have. If you have a 304 Jeep then by all means find a 305 Chevy TBI engine and get all the parts from there. Really only 2 things need to come form like size engine and that is the ECM (which chip could be changed later) and the TBI unit because different size engines have different size injectors so it's much easier to start with like parts.

Getting the harness is the hardest part so take your time. You can get all the wires needed but some may need to be cut and spliced later. For instance the ALDL port that a mechanic hooks up a scanner to. Get as much wire as you can reach, cut, don't worry about it.

Now for getting the harness, start at the ECM, get it, then follow the wires out the firewall and get all the wires that lead to all the sensors, then grab all the sensors. There will be a lot of extras just take them all and we will straighten them out later. One wire will lead all the way to fuel tank but you can cut this to save time and then lengthen to your truck later. Unbolt all grounds you find as you will use them as is later. Grab the relays, usually 2 and sometimes 3 grab the mounting brackets as well, they are all handy when this goes together. One wire is called the "Crank Wire" it will go to the starter. If it's to hard to pull the starter no biggy just cut the wire as close as you can.

If you take off the TBI unit try to get all the hoses, braided wire hose fittings etc all the way as this may be very helpful and save big bucks when buying EFI rubber hose at $7. a foot. You could get them all the way to the tank and get the tank too. If you have the tank it has an internal mounted EFI pump that can be reworked to mount in your tank. Or go external.

Take out the distributor as it will work if you machine a hybrid to your stock bottom. If not it still has the EST module needed for timing control.

Grab all brackets that hold sensors as they can be reworked and be very handy.

Grab the air filter, Thermac heat riser valve and hose to air cleaner. They work great in cold weather. Usually all air cleaners are plumbed to cold air so gram all the cold At tube as well. Look around and you will find a plethora of GM air filter combinations with cold air tubing and Thermac valve for hot air. I really like the Thermac from GM because it does not even use a vacuum line. Just heat. Seals shut when hot and all you get is cold air from the tubing you gathered.

Parts check list.
TBI unit has TPSW, injectors and IAC on them. Grab anything that may be useful hooking up you throttle cable.
Harness
Distributor
MAP sensor
Knock sensor
ESC sensor
EGR soliniod usually next to ESC sensor on trucks.
CTS Coolant Temperature Sensor. If it's to hard to get to no worries it's about a $10 part new and they do corrode and wear out.
O2 sensor. Again if to hard they wear out and are in the $25 range.
ECM
Speed sensors are usually built into dashboard or transmission of transfer case so they usually won't work anyway.
You really don't need the oil sensor stuff as we usually wire it out of the harness.
If your going to use a GM transmission then by all means get the wires and connectors. Manual, turbo 350, 700r4 are all easily covered by any ecm. Now if your going to use a 4L60e or 4L80e then you will need a ECM that is capable of handling that transmission.

I'll be editing this as I do my next conversion so this is just a start.

You can get started on this but you'll need some wiring diagrams. They are all available here:
http://www.gearhead-efi.com/Fuel-Inj...Information-42

OK Once you've got your harness stripped from the donor vehicle you'll end up with an ominous octopus looking like this!
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303067935

Take your time and remove all the convoluted tubing/covering. Using a razor blade is what I do just take your time and don't cut any wires underneath. What you end up with is like this. Your harness and all the crap you cut off.

http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068012

While your removing the convoluted tubing it has black electrical tape on each end you want to remove as well. But look for these factory splices that attach 2 or more wires together and leave them. The tape used here from factory is more like a duct tape than electrical tape, that will help you identify the ones to keep for now.
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068069

If you have your parts or a complete intake we are going to use this for the mock up.
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068147

Using the ECM as well! Mine is bolted to the wall because I do a few of these but laying on the bench is fine. Start here and plug your harness into the ECM!
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068272

The fish out the connectors and hook them up one at a time to the sensors. The plugs are all unique and can only get plugged into where they belong. You'll see the wires hanging to the floor and about half of them are going to be removed. The others are to power, ground, fuel pump VSS etc...
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068365

I've done a few of these over the years and built a test bench with 12 volt power, ECM bracket to mount ECM, fuel pump, relays, O2 sensor. Along with this for pictures is some of my equipment like laptop for recording data and checking sensors, JimStim Stimulator for sending signals to ECM to check them. Oscilloscope for checking electronic frequencies which has helped find many glitches in conversion systems which may get some electrical noise messing things up from mounting a sensor to close to spark plug wires etc...

I have a lot of fun with it and have helped Friends make sure their harness, ECM and sensors are all working correctly before installing it on the vehicle.
http://www.gearhead-efi.com/Fuel-Inj...1&d=1303068418

After a few hours work you have a harness ready to install on your vehicle.

http://www.gearhead-efi.com/Fuel-Inj...0&d=1320981962

All wiring diagrams for the 7747 can be found in our photo gallerey/library.