Did a quick search but couldn't get a clear answer. Lately I've been getting poor gas mileage (2 tanks ago ~325 miles, last tank ~300 miles, this tank ~275 miles) and it just seems to be getting worse! I checked my air filter, and spark plugs, and my oil is good no leaks everything seems to be fine. Could there be a problem with my O2 sensor, would getting a new one in there help? How can I check to see if this is what I need? I ran some Synthetic Fuel Injector cleaner in my last tank of gas too. By the way I have a 95 LX Coupe w/ F22B2 if it matters. Any help would be a appreciated.

 

any codes ?? ( chk engine lite on ) ?
have you checked timing ?
what is the idle at ?
any vacc leaks ?
got good tires?
does engine run smooth ?
have you had the a/c on more now than 2 tanks ago??
driving same roads? same way ??
what brand plugs in the engine ?
what viscosity oil ?

there are a lot of things to take into considerations when it comes to fuel mileage..

 

if computer is not throwing any codes you might want to check your t-stat to see if it is working proerly. I had a tstat that was sticking open and my MPG dropped from 25 city down to 23... car was not tossing codes but no heat on really cold cold days... replaced t-stat and MPG is right back where it should be.

Also you can test your 02 sensor before going the replace it route.....


other things to do

Clean intake
run FI cleaner through gas (I use 1 can of sea foam)
check your air filter and make sure it is not full of crap

 

well i took it in to get a diagnostic test and nothing came up. the guy at autozone said it could be my fuel filter, then he checked my pcv valve and noticed it wasnt rattling like it should, so he told me to just replace that first and see if it helps. so i got the pcv valve, but i just filled my tank yesterday so lets see how much it helps

thanks for the respones

 

Your PCV valve has little to nothing to do with gas mileage. Your o2 sensor is ok as long as the check engine light is off
The biggest things you need to check out are
Sparkplugs
Tire pressure (32PSI)
air filter
clean out trash and un needed junk from the car
DO THE SPEED LIMIT
brake less and accelerate slower

 

^^I've been doing that ever since i noticed my gas mileage was going down its something else

 

It may be this new 10% ethanol summer gas.

 

do a valve adjustment.