When I first got my 1993 honda accord lx my gas was amazing, but now it's just disgusting. I filled my tank yesterday and drove for maybe a half hour I'm on E... I don't know what can be causing this but I hate it. If you guys have any ideas on what could be the problem please let me know. Thank you, Jess.

 

Jess2009,

Let's go over the most commonplace causes for a sudden and pronounced drop in fuel mileage:

1) Bad PCV Valve- A bad PCV valve can cause excessive oil leakage and consumption, oil deposits on your air filter, excessive fuel consumption and engine stalling. Inspect your air filter for any oil deposits (refer to this Accord Air Cleaner diagram if necessary) and also note whether or not you are experiencing excessive oil consumption/leaks.

2) Throttle position sensor, coolant temperature sensor and knock sensor- Inspect these sensors, or have a mechanic inspect them, in order to determine if they are faulty and require replacement. These components are all crucial to maintaining a healthy air/fuel ratio and can cause excessive fuel consumption if any one of them is faulty.

3) Ignition system components- Bad spark plugs, wires, coils, etc can cause poor fuel mileage as well as erratic idle speeds, hesitation upon acceleration and sometimes even surging/pinging.

4) Emissions control system components- Things like your Accord's catalytic converter, o2 sensor, and EGR valve can all cause poor engine performance and fuel economy when they are bad. Inspect all of your car's vital emissions control components to ensure healthy operation.

5) Fuel system components- Injectors, fuel pumps and filters can all cause poor fuel mileage if they are clogged or faulty.

6) Tire pressure- This is perhaps the simplest of all points of inspection but you'd be surprised how adversely impacted your fuel mileage gets when your tires are improperly inflated.

Check out all of these components and I'm almost positive that you'll find the culprit behind your sub par fuel efficiency

 

The most common are air filter dirty or fuel filter.

 

Thank you everyone for the help. I just wanna say I have had a bunch of work done to the car such as:

full exhaust
catback
tune up
plugs
wires
cap
rotor
distributor
balljoints
oil pan
fresh oil change
brakes
radiator hoses

and probably more I just can't think of anything else

oh and the car was out of time when I bought it but I got that fixed about 3 months ago

It recently just got inspected August 15, 2011 so I don't know what else I'm doing wrong here?

 

Did you get the filters replaced?

 

Not sure If I got the filters replaced honestly but this morning I put 12 dollars in put me at half a tand I drove 20 miles to get home and I'm on E already. I was mainly on the highway I was doing in between 50-65 I don't beat on the car at all I'm just thinking about selling it...