vile1

Im getting 300kilometers per tank. That's 11.2 MPG.

All this time i thought i was getting decet mileage and DUUURRR the gauge is in kilometers.

The car is a 1986 Mazda RX-7 non-turbo. Is there ANYTHING i can do to increase the mileage? Its RAPING my wallet.
Maybe clean the injectors? But can i use that injector cleaner you put in the gas tank in a rotary? Will it damage it?
I already changed the plugs/filter/fuel filter I have no idea what else it could be....

slo

iTrader: (1)

defanatly change the 02 sensor, you possibly have clogged cat converters.

does the car seem generaly under powered?

How did you get an RX in san diego with the gauge exclusivly in kilometers?

SpooledupRacing

change oxy, see if your exhaust smells like gas, check/replace cats, add some jectro or techtron to the gas tank

SirCygnus

iTrader: (1)

its cali. you know how jdm crazy those losers are in sandiego.

change the 02 sensor, and run a **** ton of stp fuel injector cleaner in the tank wih some chevron with techron. then bash the living crap out of it for the whole tank, and i mean bash it. redline that beast any chance you get to get your injectors a good workout.

SpooledupRacing

dont waste money on the stp go with the techtron aditive at like 1/4 tank and get on the highway and beat the snot out of it

Dave

vile1

Actually, the car is an import from Canada.

When I was looking at buying an FC i found this thing and it was GORGEOUS.

1 owner, a Doctor, kept meticulous care of it, only had 66k original miles on it when i bought it.
Thats why its in Kilometers. **** that JDM bullshit

When I start it and such and idle, it smells like gas fumes. is that the cat's being clogged?

I'll change the oxygen sensor and add that techron/whatever to the tank as well.

The car doesnt SEEM underpowered. It has a VERY slight hesitation at 3200-3500RPM but thats it (and only when it's cold)

Aaron Cake

iTrader: (1)

Don't waste time with injector cleaner. The only thing it will remove is money from your wallet.

If you want your injectors cleaned (a good idea for sure) then you will want to send them to an injection shop for proper cleaning.

Since you have already replaced the plugs and wires, you have a good start. Now test the coolant temp sensor, adjust the TPS, check the timing and do everything specified in the 60K tuneup.

The O2 sensor won't matter much.

Aside from that (and assuming the engine is in good shape mechanically) then the next thing you have to adjust is your driving habits.

Also, see the FAQ for several good mileage topics.

ericgrau

iTrader: (1)

The techron injector cleaner stuff actually works, though it won't clean really bad injectors. It's worth a shot though it might not be the problem. O2 sensor matters too. You'll never get 11.2mpg no matter how bad you drive. Something is wrong.

How did the smog test look?

Twofer

Yeah... wait what?

Hey vile1, if you can make it, the San Diego RX club meets this saturday at Fuddruckers in Mira Mesa. I'm sure we could give you some pointers.

https://www.rx7club.com/west-rx-7-forum-193/san-diego-meeting-next-saturday-583366/

asiansuperstar

Where can i get a good O2 sensor?

Aaron Cake

iTrader: (1)

For the $30, replacing the O2 sensor is worth it but don't expect any real mileage increase unless 90% of driving is done on the highway. These cars have a very primitive closed loop system that almost never is active in stop and go traffic.

Depending on the state of tune of the car, it can be easily possible to get 11MPG due to bad driving. In fact, it's easy to get even less then that...

Sideways7

iTrader: (7)

Techron is useful, but only if used over a period of time, and as preventative maintanence. Nothing will really clean your injectors once they're clogged.

slo

iTrader: (1)

The O2 sensor can be had for $ 20 at autozone. Get the universal one that you just have to crimp the oem connector onto.

At the time I did about 50% driving on the freeway. My car at the time was avg 16, and would barley do 18 on the freeway at 75. The 02 sensor alone brought that to 19 AVG, 24 freeway at 75.

That was on my dads compleyely stock NA when I borrowed it for 6 months.

ericgrau

iTrader: (1)

No, quite the opposite. I wouldn't use Techron more than once, then give up after that. If your injectors are truly & horribly clogged then you do need to get them cleaned. But a lot of people have had good results from using Techron additive. For preventative maintenance fill up with Chevron, Shell, 76 or Texaco (www.toptiergas.com). The good gas brands already have all the additives you need. Chevron isn't BSing you when they sell bottles of "Techron Concentrate"; it really is roughly the same stuff they put in their gas.