poor gas mileage

[iammikesevvy]

i have a 95 gsx and right now i have driven 93 miles and have a quater tank left...i have apexi exhaust and 16g turbo at 17psi. i think the boost is causing the poor gas mileage but would it make it that bad?

 

[hubz91talontsi]

tire pressure? A/T or M/T? This a high speed highway drive? DSM's suck past 65 unless you extend the 5th.

 

[Daveed]

bad o2 sensor will reduce fuel mileage.

 

[iammikesevvy]

the tire pressure is good i dont know what M/T is and it is a mix of both highway and street. Is there a way i can check the o2 sensor?

 

[turboglenn]

the tire pressure is good i dont know what M/T is and it is a mix of both highway and street. Is there a way i can check the o2 sensor?

You can use a voltmeter on the O2 signal wire at the ECU in the car ( i forget the color and name) but if you look up road race engineering's SAFC install and tuning page it will give you the info on where to find the wire. Then hook a avoltmeter to it and observe teh behavior. when cruising or at idle the needle on teh voltmeter should swing up and down..When Coasting to slow down with the RPM's above 2-2500 the voltmeter should read almost nothing, then at Wide open throttle you should be seeing .94-.98mv or more

If it oscilates up anjd down during cruise and idle it is working correctly. if not and your voltmeter just reads a a stead number most all teh time or doen't seem to change much, it is bad. DOn't replace it with a universal, most of them don't have fast enough switching for good closed loop operation ( unless it's an NTK/NGK brand..the bosch's suck)

this link has links to the page you will need to read up on the AFC blue wire mod that allows you to monitor o2 volts. Just use a cheep needle voltmeter in the same fashion. ground the ground or common lead to the frame or a bolt that's attached to the body. Then hook the positive one up to the wire mentioned in the article and observe as described above.

 

[ROOKIE1]

automatic or manual transmission . Boost leak test . Tune up .

 

[iammikesevvy]

manual and thanks turbo glenn i look into that

 

[Defiant]

If you can't fill the tank and do the mileage math, we won't discuss it.