1993 240SX-19 MPG WTF!?

[Schrute Farms]

Title pretty much states it all. I have a 93 240 and it gets 19 miles to the gallon city and 22-24 hwy... All the emissions stuff has been removed. I am thinking that is what's causing the ****ty mileage. Is it possible to have none of the emissions stuff and good mileage? Thanks

[Crazyirish]

A lot of things can adversely affect your mileage. I'm not saying its one big thing, but 5 or 6 things could be a little off. Check for any ecu codes and try a compression test.

[Schrute Farms]

A lot of things can adversely affect your mileage. I'm not saying its one big thing, but 5 or 6 things could be a little off. Check for any ecu codes and try a compression test.

No codes. I will compression test her and get back to this thread with the results. It will be a while though probably.

[Shusaka]

wow i wish i got that kind of mileage. my girl gets 17 city 23 highway and its a bone stock S14, i blame driving habits, lol drifting = bad mileage, i have made peace with that

[theother1wstolen]

and just in case you were wondering, off the top of my head things that will affect it noticeably, oxygen sensor, spark plugs, CTS, TPS, tire pressure, driving habits, vacuum leaks, intake leaks, (maybe exhaust leaks too but im not sure about that one), improper fluid levels, almost every sensor, basically everything except the color of your paint. unless its purple. its not purple is it?

-edit- i removed all of my emissions stuff, put on a header, test pipe, and high flow muffler, etc. and i get 32ish mpg average city/hwy
Modified by theother1wstolen at 12:16 PM 12/10/2008

[Schrute Farms]

and just in case you were wondering, off the top of my head things that will affect it noticeably, oxygen sensor, spark plugs, CTS, TPS, tire pressure, driving habits, vacuum leaks, intake leaks, (maybe exhaust leaks too but im not sure about that one), improper fluid levels, almost every sensor, basically everything except the color of your paint. unless its purple. its not purple is it?

-edit- i removed all of my emissions stuff, put on a header, test pipe, and high flow muffler, etc. and i get 32ish mpg average city/hwy

Modified by theother1wstolen at 12:16 PM 12/10/2008

No the car is red lol...I think I have a vaccum leak. The car idles around 600 and has really seemingly low power. Can I pressurize the intake to find vaccum leaks much like you do to a turbod car? I tried spraying carb cleaner all over but couldn't find the idle rising at all.

[theother1wstolen]

http://www.plumbersurplus.com/...4.jpga torch kit like that works great with a small propane tank for finding vacuum leaks

[justin240]

if it does have a vacuum leak that whats causing your bad gas millage, not all of it but that's a big part of it

[del82]

If you've removed the EGR system, you'll lose some gas mileage. The engines are actually designed to mix the exhaust gas with the incoming air charge, reburning the leftover hydrocarbons from the first burn. Without the EGR, not only will you lose mileage, but your HC output will be way, way higher.

That's why I kept it in good shape on my Supra nothin' like an insanely heavy car with a straight six pushing 28mpg highway. That's still hard to beat, even with today's engine technology. Especially funny considering I had 4.30 gears in the rear end...

[spank044]

Title pretty much states it all. I have a 93 240 and it gets 19 miles to the gallon city and 22-24 hwy... All the emissions stuff has been removed. I am thinking that is what's causing the ****ty mileage. Is it possible to have none of the emissions stuff and good mileage? Thanks

I get better mpg than that on 27 psi with no egr and a safe rom tune. Have you done a tune up lately? Tire pressures, good lube everywhere? The little things are what matter the most. Under inflated tires can cause a 10% fuel loss due to the extra friction. I say give it a true tune up with new ignition (cap,rotor, plugs, wires), fuel filter, and fluids, then come back with your numbers. I bet you gain 5-10 mpg.