Poor Gas Mileage
 

So I don't know what to do anymore and it's getting really pricey on gas these days.

I have a 2002 Acura RSX-S. I used to average 8-10L/100km. Now I'm at about 12-13L every 100km.

I already changed my Air filter, oil change, spark plugs. No I don't drive aggressive. I've started to notice this since september but it hasn't went away.

I have no CEL, no I don't think changing the primary o2 would help. What else could I do?

Winter gas when it gets warmer and they start using summer blend gas you'll see better mileage.

Everyones mileage drop during winter time
Posted via RS Mobile

Stop complaining, I have a 165L tank and get about 18mpg on the highway. I daily from Port Moody to Abby.

it'll be like this till the weather gets warmer again, heck if I drive my 350 without really warming it up, it'd be at 55L/100km for the first 5-10mins.

Yea I drive 03 rsx as well, noticed poor mileage during winter as well.:okay:

See.lai + sports car............you're surprise your gas mileage is bad? :troll:

Not disagreeing with the poorer winter gas mileage at all, but with my pos beater, I'm only seeing ~10 - 15% reduction in my gas mileage, whereas the OP is seeing a 30 - 50% increase.

Sounds pretty crazy if you ask me. Does the OP mostly only do short drives?

O2 sensor?
Posted via RS Mobile

pcv valve is often overlooked
fuel filter too

I'm pretty sure winter gas doesn't affect it that much. Last year around this time, I had 9-10L/100km. So I don't think that would affect it.

I noticed this change around september, so I don't think this "winter" gas would be in effect at that time.

Like I said though, the CEL isn't showing, why bother with the O2?

Thanks, I will check pcv and fuel filter.

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Most are of my drives haven't really changed. Usually 15km each trip. Not sure if that is considered a short drive or not.

Because O2 sensor can be sticky and it still will not have a CEL. It is usually in the marginal scenarios like this. I don't know about Honda/Acura's diagnostics tools but BMW's diagnostic headunits can show the reading changes while the car is being driven. If the sensor reading is not changing as quickly, it is time to change. CEL means failure.. not necessarily non optimal working conditions.

[QUOTE=see.lai;8151885]
Like I said though, the CEL isn't showing, why bother with the O2?

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Suurprised no one has said this. Check the tire pressure.
Posted via RS Mobile

Do you have a CAI?

Lazy 02 sensor im betting
Posted via RS Mobile

Running winter tires?

I'm still getting close to 400km a tank
Posted via RS Mobile

My gas mileage has tanked since winter gas/tires... Getting 11-12L/100KM now, Was getting ~9.2 before winter gas/tires. May just be that

Problem Solved..




:troll:

Thanks for the help guys.

I checked tire pressure bi-weekly. I have a short ram intake, but that's not really the point because I had way better mileage last year. Everything is the same, tires are the same as last year.

I will check the O2 as well then. I just didn't want to buy and replace if it wasn't the problem.

check plugs and oil, make sure your trans oil is in good shape otherwise change it out.
you already checked tires but also make sure that your bearings are in good shape and that your brakes are sticking.

you cat also clogs slowly over time but i wouldn't recommend changing it until you blow out your o2 sensors.

check all you belts and pulleys to see if anything is causing extra restriction and clean out air filter.

Driving hard buddy? My sister gets about 480km - 500km+ on hers...then again she has a feather foot

Do you have a fat gf?
Posted via RS Mobile

Kidding aside ... I have the same issue....:(

the chances that it's winter vs. summer difference is minimal - this is a huge decrease in economy.

the winter/summer argument is also slightly nullified by saying that colder air in winter makes for higher O2 density, thus increasing economy (hence why so many have CAI)

likely a sensor is bad/needs cleaning, so go to a shop accordingly if you don't know your sensors/how to test/clean them

My fuel economy improves by 1L/100km in winter when I put stock wheels and tires on :troll:

I recently took my fuel injectors out and cleaned it, getting much better mileage.