
If you are an unlucky guy like me, then your car is carbureted. If your car has a 4A-F (not 4A-FE), then you are equally unlucky. Fortunately for us, we can somewhat easily rectify the situation by converting to EFI.
This requires several things. Firstly, the fuel pump in the EFI'd Corollas are of the in-tank variety. This means that the easiest way to swap it out is to swap out the entire fuel tank. I highly recommend either running the car to as empty as possible, and even then, finding the drain plug located at the underside of the gas tank. We thought there was much less gas than there really was, and had to deal with a seriously scary amount of fuel coming out. Again, consult the BGB for the corolla to see what the steps are to remove the gas tank. Basically, you drain the tank, disconnect the fuel lines, disconnect main filler hose, and unbolt the two (2) big straps holding the tank to the underside of the car. Once you do all this, make sure that you have removed all the bolts/fasteners holding it to the car. It is also held in place with some really sticky tar type stuff, so some gentle prying may be necessary to get it to come down. You will also need to remove the rear seat cushion (2 metal tabs at the front edge of the seat) to access the fuel level sender connector. Disconnect those as well by removing the circular metal cover and unplugging the harness.
I purchased a tank off of a 1990 Toyota Corolla LE (through my local auto wreckers), which came equipped with the 4A-FE engine. We also chose to replace the in-tank fuel pump with one from a Toyota Supra Turbo (7M-GTE motor). Overkill, you might say, but lean conditions and fuel starvation are no laughing matter. The Supra Turbo pump is a direct bolt-in affair, although there are also several other options out there in the aftermarket, and I'm sure that you could also use the N/A Supra (7M-GE motor) one as well.
Another item you need to swap over is the main fuel line and fuel filter. The main line for the EFI-equipped cars is high pressure, and as such, requires a high pressure line. The carb'ed cars had low pressure lines, with dinky little clamps holding them on. You will need to purchase the main line from an EFI'd corolla, again, a 1990 Corolla LE should be just the ticket. To remove the old line you will need to unbolt several places where the plastic cover piece hides the hardlines. It is much clearer to do when you are actually underneath the car. You don't have to worry about being too careful while removing the line, as you will be throwing this away anyways. As the engine bay is already empty, you won't need to detach it from anything up front. Be careful not to damage any of the other lines, however.
Grab the new high pressure line, and run that in the same location as the old one. You will notice that the new line is all bent and contorted, but that's so that it can conform to the underside of the car. Carefully put the new line in the same place, and snap/screw the cover in as you go to keep it in place. When you reach the gas tank location, you will notice that you need some other lines to continue it to meet the new tank. This will depend on how much of the EFI'd setup you got with the new tank. On my application, I had to purchase the tube sub assembly and bracket for the fuel pump (#23091-16030 and #23206-16430). The sub assembly connects the high pressure line to the fuel pump itself. On my junkyard tank, the line was mangled, requiring a new one. Everything should connect together nicely.
Now, before you actually mount the tank back into place, you will need to crawl back into the car and install a couple of wires. The fuel level sensor can be attached to the same location, although you may need to splice a few wires together, but check your wiring diagram to be sure. One of the 2 new wires you need to run is a ground for the pump. I just ran a wire to an existing bolt and scraped off some paint to ensure a good ground. The second wire is a power/turn on lead for the pump. Again, check your diagram to see which one it is, but this wire will need to run from the circuit opening relay (which is piggybacked on the ECU's exterior) to the fuel pump. If this wiring scares you, you should either find a friend who knows wiring, or turn back now. This is nothing compared to wiring up the rest of the car.
Once you have the wires ready, you can crawl back under the car and mount the gas tank. Since the new one is empty, it should be relatively easy to move around. Lining up the tank with the straps can be difficult, and there really isn't much room for 2 people under there. Before you begin strapping everything back up, reconnect your main filler hose, make sure that you can access the pump wiring from up top via the access hole, and ensure that everything else looks kosher. Now, to reinstall the tank, it can be sometimes easier to use a spare jack w/ a piece of wood blocking to help support the tank. Although lighter, it can be somewhat unwieldy. Once you get the straps in place, jack up the tank to hold it where it needs to be, and bolt the tank in. Again, check the torque specs in the BGB, and once you check to be sure everything looks good, go back up top, and connect the remaining fuel pump wires.
Now, back in the engine bay, you need to remove the stock charcoal canister and replace it with one from, you guessed it, a 1990 Corolla LE, or similarly equipped EFI'd Corolla. Straight swap out affair, but you need to do this to properly connect the return lines. Also, this canister will provide the appropriate bracket for the 1988 Corolla GT-S (or equivalent) fuel filter. This is where you need a nice, new banjo bolt and washers, and this will connect to the fuel filter, which in turn connects to the charcoal canister bracket, which connects to the leg bone, the leg bone connects to the, knee bone...