Eats gas like V8 5.0L
 

I have a 1995 240sx however it eats gas like v8 5.0L
I can figure out what is the problem I change fuel filter I put in fuel filter from 300zx, oil change etc……… however I had full tank of plus gas yesterday and I drove 120 miles “highway” and my car eat half of the tank that can be good and I was not pushing it at all.
If any body can help me to figure out what it is that would be great.

Thanks:

check 02 sensor

just personal curiosity, what would an o2 sensor do to the gas mileage? please dont take offense to the question.

A bad o2 sensor will make you run rich as hell and use more gas.

dirty or leaky injectors also will waste gas.

If, by 02 sensor, you mean "mass airflow sensor" (one and the same thing?), I think the engine light would be on.

A 02 sensor is located in the Exuast Manifold. It Relays the Air to fuel Mixture to the motor. If its bad it will Tell the computer the car is running Lean and add more gas. Thus killing your gas mileage.

in my experience, the gauge isnt accurate at random times. did you refilled to see how many gallons it used in the 120 miles?

no i did not i should do that

like i told the other guy with bad gas mileage, this is something you should bring to a dealership. and ask them to hook it up to an exhaust gas analyzer which will tell you if your running in a rich, lean, or misfire condition...and then have them hook it up to a scope and check all the sensors, and then you will have an accurate why ur car is doing that...the amount of fuel used is determined by so many factors, you could have a bad vacuum leak, air bypassing the maf or speed density sensor causing your 02 sensors to sense a lean condition and dump more fuel, could be a bad 02 sensor, it could be a egr vavle open or stuck closed, it could be a bad tps sensor...like i said there are alot of things to check be smart and spend the money b4 something goes horrible wrong with your motor

how much somethink like that will run for

maybe an hour/hour and a half labor, but its worth knowing exactly whats wrong with your car

The mass airflow sensor is mounted right after your air filter and the o2 sensor is mounted to the exhaust or headers. so, no they are not one in the same. hope this helps.

Ah, my bad then. Thanks for the clarification.

hey, i dont mean to thread jack, but when you wire an AFR guage, which o2 sensor do you mount to?