I have a '91 with 145,000, my dad has a '90 with 75,000. He get 38+ I get 28 mpg.

My plugs and leads, ignitor, fuel and air filter are new, where should I look next for the gas hog? I recall having a vacuum gauge will help in isolating some parts failures in fuel delivery?

 

Check timing

How do u drive?

High rpms = bad mpg

 

it would help to know what car and model.
also, the transmission you are using and whether it's auto/ manual.

 

o3 sensor

 

No, its a 91. O3 sensors wont work. <joke

 

your burning oil in the camber to, valve seals need replacing at 100,000 no matter how its drivin, do that and nothing will get into the camber but gas and air, oil even if no smoke will lower MPG big time.

also you tank might have bad gas fuel treatment is also recoomended

 

Dad probly has a lighter foot.

 

Change your cap and dizzy rotor? I did that and car run much smoother and gas mileage is now 40+ but then again I drive very slow.

 

Thank you-forgot to mention both are DX manuals-never have had an automatic-tried SeaFoam, use Mobil1 in mine Redline in his, we have similar driving habits, 13 inch aluminum wheels on his steel 14 on mine both are narrow cross section tire, new cap/rotor on both, good bearings throughout, new 02 sensor on mine, non leaking injectors too. I have not heard of valve seats being gone at 100,000 and oil use is minimal. Still I could do the seats.
I have a rebuilt pair of injectors-can I install them and reuse the keeper plates? Or is that a new item only replacement when you change out your injectors?

Any preferences for clutch brands when replacing?