If your vehicle is 1995 or later, you will need a scanner to retrieve the trouble codes. There are auto parts stores that provide computer scans as a free service. If your car is earlier than 1995, the codes can be retrieved manually, but you will need a manual for instructions and to know what each code means. Manuals (Haynes or Chilton) are available for $11 - $14 at most auto parts stores. Or you can check at your local public library to see if there is one available for checkout.
From '96 up the Tauri (and all cars) had OBD2 systems, which (I believe) can not be read without a scanner. Many chain auto parts stores will check codes on these cars for free.
Dis-connect the battery, and wait a couple of minutes before you start working on it.
If your vehicle is 1995 or later, you will need a scanner tool to pull the trouble codes. AutoZone and similar auto parts stores offer free scans. If your vehicle is 1994 or older, you can manually pull the trouble codes. Check out a repair manual (Hayne's or Chilton's) at your local library - chapter 6 has all the details on how to do it; also what each code means and how to trouble shoot.
Answering "How can you diagnose a 1998 Honda accord without an OBD scanner?"
You can't. It requires a scanner to read them.
1995 Mystique automatic 4 cylinder probably has a Ford CD4E transmission with an internal filter that cannot be changed without a major disassembly of the trans. which makes it impractical if not impossible for a home mechanic or fast lube shop to do. Either get your transmission rebuilt or replaced while you have it out and save yourself some grief.
connect a diagnostic scanner and see what fuel percentage is showing.
You can't, you must use a scanner.
That's the lock-out that keeps you from moving the transmission out of Park without the brake being down. It should have done that its entire life (my '95 Mystique did), and isn't anything to worry about. The codes being read wouldn't have had anything to do with it.
there is no correct way of monitoring a oil level without a dip stick my suggestion is go get another dip stick even if you have to buy a new one the price is less that replacing the engine
Unfortunately, the only way to retrieve trouble codes after 1995 is with the OBDII scanner. The good news is that there are some auto parts stores that will scan it for you free of charge. Or, you can buy a simple OBDII scanner for about $60.
No obd2 requires a code reader or scanner.