If you are new to the fox body game, you may be feeling understandably lost. There is so much information, and mis-information out there in the vast seas of the internet. While every single car is different, and has different needs, we will try and frame up the best first steps in getting going with your fox body.
#1 Fix what is broken: Being that the newest of these cars is 24 years old, there is bound to be something that needs replaced. Could be a window motor, control arm bushing, cracked headlight, bad door lock actuator, etc. Grab a note pad and look over every inch of the car, making notes along the way. Obviously safety items like brakes need to be addressed first. Check your ball joints, tie rods, and wheel bearings closely; make certain the car is safe. Again, every car is different, so if it came to you with a broken T5, you already know your first step.
#2 Maintenance items: Especially if you don't have any history on the car, start with the basic items. Do an oil change (5 quarts) with a name brand oil and use a Motorcraft FL1A filter. Next up, change the transmission fluid. The T5 holds 5.6 pints of ATF. We like either the Castrol or Valvoline Max Life synthetic ATF in them, with the same fluid being used for an AOD (12.3 quarts). DO NOT USE GEAR OIL. If your car has an AOD, have a competent shop perform a flush on the trans, to get all of the old fluid out. Moving back, change the rear differential fluid using 80W90 gear oil, and four ounces of friction modifier. Inspect the coolant, brake fluid, and power steering as well. Any one of these can be in poor shape, but can also be flushed. When in doubt, change it out. All of these fluid exchanges will help prolong the components they lubricate, giving you some peace of mind.
#3 Tune up items: Now we are really getting somewhere. Time to get the old girl back in shape, and running tip top. Here is how we do a tune up on a newly acquired fox: spark plugs, spark plug wires, distributor cap, rotor button, PCV valve (remove and clean the screen underneath it with brake clean), fuel filter, and air filter (or clean the K&N).
#4 Other adjustments: The next steps go a bit deeper. First thing is to check the timing, just to see where it is at. For staying stock, set it at 10 degrees with the spout connector out, for some extra ponies, bump it to 12-14 degrees, but be prepared to run a higher octane fuel. Next up is the TPS (throttle position sensor). With the engine running, check the voltage using the green wire, and grounding on the engine/body somewhere. Set the voltage as close to .98 as possible for optimum performance, while it can be tough to lock it there exactly, make it a point to stay under one volt. To make the adjustments, loosen the two screws and move the sensor around to change the voltage, it may be necessary to enlarge the holes slightly on the TPS, to get the required voltage reading.
With all of the above completed, you will have a strong performing fox body, that is ready for some additional upgrades. Just don't go throwing speed parts at a car in dire need of routine maintenance, you will most certainly regret it. This will also give you a solid foundation for knowing what has been done to the car, should you run into problems down the road. Knowing what is new, helps shorten diagnostic time.
For part two, we will get into the first mods for a stock fox body (if there is such a thing). CR