Ok I tuned up my jeep about a month back, hoping to gain some mpg.
Changed the plugs, oil, oil filter, air filter and added a muffler and tail pipe.

now the cat is quite rusty but seems only the outer shell is falling apart. Need to change the wires, but other than that the fuel filter is the only other thing I didnt change that I can think of.
Also it has a long crank so im figuring getting new wires on their is the first option I should aim for but any other suggestions welcome.

 

When I bought my Jeep l changed the fuel filter and It made a difference on my Jeep. The old filter was very dirty, but now my injectors need a cleaning. But a dirty fuel filter does make a difference.