I have a 96 Jimmy that has a few codes coming up. The truck runs ok, and it uses alot of gas...
The codes are:
P0175-SYSTEM TOO RICH
P0146-O2 SENSOR CIRCUIT NO ACTIVITY DETECTED
P0152-O2 SENSOR CIRCUIT HIGH VOLTAGE
P0172-SYSTEM TOO RICH
P0300-RANDOM/MULTIPLE CYLINDER MISFIRE DETECTED
If anyone can help out with my problem I am greatly appreciative.
Thank You..

How long has it been since your last tune up? And also what brand of cap rotor and plugs did you use. Also a proper fuel pressure and leak down test would be helpful.