i have a 91 camaro rs 3.1 v 6 currently i'm getting about 15 mpg and I know it should be higher. Also when i'm driving i'm getting a stuttering feeling when i'm driving. It almost felt like it was misfiring, but this doesnt happen consistently. I checked my fuel pressure regulator and confirmed that my gas was not leaking into the vachumn line. I checked and cleaned all of the injectors. i applied a 12 v sorce to each injector and they all clicked i also tested the resistance and they all tested between 11 and 13 ohms. one did test 19 ohm's though. I have a new fuel filter already installed and i have a new O2 sensor

 

Distributor cap, rotor, timing, TPS, coolant sensor,check 'em all.

 

Your injectors are bad. Multecs should be 16 ohms.

RBob.

P.S. Your 3.1l is a MPFI engine