Before anyone jumps down my throat, I did a quick search but there was no great answer.

I have been getting a steady 20 mpg for the type driving I do for the longest time. Last time I filled up it was the same but .... I needed to get gas today and just like I thought (watching my odo. and my fuel gauge), my mileage is down to about half (10 mpg). I changed nothing in the week before. I looked under the car and around the engine to see if I have a leak but none showing. The car is running fine and no OBD lights. Any thoughts?????

 

What kind of mods you got on your car?

 

Could be your MAF causing some small erorrs, but im proly wrong. Lately there has been alot of posts on MAFS and concerning gas MPG. and it seems that everyone has responmded with a bad MAF or somethin in that area.

 

somebody stealing your gas bro.....lol. good luck if it isn't that.

 

wow, for that kind of mileage your car better be doing 9 second quarter miles and rated at 700 hp.

 

10 mpg WTF? This is not normal. It could be your MAF, but I strongly believe something else is going on. Good Luck bro!

 

Before you become paranoid, check the little things that can decrease your mpg such as tire pressure, air filter, etc... I average 14mpg, but thats from NYC traffic and automatic so i cant really except too much. Hope you find the problem.

 

ya yo....the weather is changing...so check out tire pressure, air filter, spark plugs, fluids, and then things like maf (and ecu) malfunction. basically if its not something mechanical like tire pressure, your ecu is trying to send more fuel to make up for extra strain on the engine (either not enough oxygen gettin to it, or very thick tranny fluid or not enough power from combustion or some wierd junk like that)

 

check for small fuel leaks around the filter and what not, believe me, its possible

 

Get a new calculator, there's no way you drop to 10 mpg without noticeing a performance problem. You also said that you watch the odo. I go at least 300 miles between fill ups. Are you saying that you only had about 150 miles when low?

 

Do the Seafoam treatment first and go from there..... good luck

 

Right now i get about 80 miles per 1/4 tank id say. Anywehre from 70-80. Is that ok or is there an issue there??

 

Saying you get x miles on 1/4 tank is meaningless. Report back after you fill the car up, drive it like you typically do until you need at least 16 gallons (ie. the better part of a tank) and report back. I've never gotten less than 350 miles out a tank on city driving at less than 40mph, with traffic and stop lights.

 

Thanks to all for your ideas. As it turns out, my sender/float must have freaked out for awhile. My mileage did drop alittle but it was just short lived. Maybe it was a bad batch of fuel. I don't know. All I know is that it's close to normal now. Thanks again.