i have a 98 civic ex with a d16 i got like 2 weeks ago. Its getting horrible mileage right now, easily under 20mpg. they didnt seem like they took care of it much. waht do you think might be wrong with it to regain my mileage.

 

As part of buying a used car. It's always recomended to check the condition of the routine tune up parts.

Check your plugs, wires, dizzy cap/rotor
check oil/ tranny fluid. All fluids actually
check air filters, oil filters, and fuel filter
check your compression, and your fuel pressure as well
Pcv valve
wheel alignment as well

and if it's a y8 don't expect godlike 40mpg that's rare. Expect 25-35 on an auto(29-37 on manuals)

 

also check all vaccum hoses mostly the one the goes to your fuel pressure regulator have seen this unplugged countless times and it will cause your injectors to just dump fuel none stop and yeah gas mileage with z6/y8 is gonna be mid 30's if you stay out of vtec i get 45 mpg but im also running a vx tranny till i get my z6 tranny rebuilt

 

When you're done with your VX tranny, how much will you sell it for?

 

Good grief, with mileage that bad I would be checking for fuel leaks.

I would do a full tune-up (plugs, wires, dizzy cap/rotor button, fuel filter, air filter, change oil/filter, change tranny fluid, run some sort of injector cleaner, etc), check your tire pressure, look for any cracked or missing vacuum lines, get an alignment. Your fuel mileage should be in the 30's easily.

 

^yeah, what he said

 

Dont forget to use a bottle of chevron techron cleaner every 3k miles! Stuffworks wonders.

 

Oh yeah it is. I usually either use this or Gumout Regane Fuel System Cleaner. I routinely get 40-43mpg on my little y7.