i have a 89 gtu. when i full my gas tank up the frest half is gone in like 50miles. i get about 160 after that. i know i dont have a hole in the tank. does anyone know y that is?

210 miles to the tank...you prolly fill up around 1/4 left so... 210 for 3/4 of the tank...16 gallon tank



makes sense







if you had a hole in your tank you would know...why would you think that

what can we say Rx7s get shitty gas milage

The gauge on the stock cluster is not that accurate. As an example, I've driven three different n/a S4's and all three have had different tendencies with the fuel level on the gauge. Personally, I prefer the quicker at first then slower near the bottom, it allows you to put off filling up longer https://www.nopistons.com/forums/pub...IR#>/smile.png



Find out you mpg and then we'll see if there's a problem.



Other ideas?

Leaking injectors, heavy foot, clogged cat, etc.

yeah you need to figure out the mpg, the guage isnt accurate enough

about 11 mpg does that sound right ?

nope it should be more like 18-20, look at changing your 02 sensor

02 sensor is where its at! *slaps j9 on the butt* good game!



https://www.nopistons.com/forums/pub...DIR#>/ohmy.png

water is more expensive than gas..... a 20oz bottle of water is a dollar, go figure....

So true https://www.nopistons.com/forums/pub..._DIR#>/sad.png

would a intake temp senser do that to my mpg?

but i will try an o2 senser

no



o2 sensor

yeah, I don't know why I didn't mention that. Those things get cooked quick.

is your car bridgeported? i never had a diffrence after cahngin the o2

mayeb i never had a bad o2 https://www.nopistons.com/forums/pub...IR#>/smile.png

It is prolly your O2 sensor but I did have a problem with my temp sensor on a different car that caused shitty gas mileage. Not the sensor that relays info to the gauge but the temp sending unit that provides data to the ECU. It failed and the signal it sent told the ECU the engine was cold all the time. Therefore it never came off of enrichment cycle. The car idled at 2000 RPM and was hella rich all the time.

Yeah, if the water temp sensor that is on the back of the thermostat housing is messed up it will trigger an error code in the ecu and put it into some crazy mode. If that were the case, there should be more problems than just bad mileage though. Have you been experiencing bad power or an inconsistent band or hesitation or anything like that?



I'm still confident the o2 sensor is affecting this. Remember that when you replace it the connection has to be pretty good. I'd even recommend getting the more expensive one that has the clip already attached unless you're handy with a soldering iron.



Redwood