Yo DAWGG,
You should get just 3 digit codes.
Ford went from two-digit to three-digit EEC IV Self-Test codes in 1991 to service the increasing number of service codes required to support various government On-Board Diagnostic (OBD) regulations. The phase-in from two-digit to three-digit codes started in the 1991 model year and is largely complete except for some medium/heavy trucks that will retain two digit codes through the 1994 model year.
Some possible codes for the EVP;
DTC 332 - Insufficient EGR flow detected; "Atop the EGR valve there is a sensor called the EVP (EGR Valve Position) sensor. It detects movement of the pintle iside the EGR valve. You can apply vacuum to the vacuum barb on the EGR valve and observe through the holes in the casting whether the valve is moving or not. It may just be dirty which requires some careful scrubbing and NO SOLVENTS. Otherwise, if the EGR valve is functioning and moving when vacuum is applied, the EVP sensor is suspect and the electrical connections to it should be checked first. (Computer needs to know the EGR valve position for emissions control)."
Source: by greystreak92 (Joe B)
DTC 334 EGR (EVP) closed valve voltage higher than expected; "...Failed sensor, & as by rla2005 (Randy) wrote; carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the ****** side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary. The EGR Valve Position (EVP) Sensor used exclusively by Ford, can be the cause of driveability problems without ever setting any trouble codes. The relationship between the EVP sensor and the EGR valve is important to understand. Either one being out of spec can cause similar symptoms. Understanding this relationship will help you to diagnose uncoded driveability problems like stumbles, hesitations, rough idles and stalling..."
Source: by rla2005 (Randy)
96 Broncos with OBD2 are year the will pop a code for loose gas cap or bad gasket. Such as, DTC P0440 & Possible Causes; "If the gas cap is not tight or the tank is filled while the key is on or the engine is idling, it can trigger a false P0440 code causing the CEL light to come on; or: The purge solenoid has failed or: The canister is plugged and not working properly..."
Do another self test for codes.
Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19
http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded