for those who will find this thread offensive because the topic has been exhausted time and time again but i need to figure out how to boost my mpg. kept records of my fillups and i'm averaging 21mpg. from what i understand, it should be around 23-26mpg. i drive an 05 tsx automatic.

i've:
- replaced spark plugs to platinum iridiums
- changed to short ram intake
- checked my tire pressures and they're up to standards
- use fully synthetic oil, regular maintenance. approx 8,000km per change.
- i've used fuel injector cleaners every 3 fill ups.

still finding that my mpg is kinda low, or at least i think it is...i understand there's variable with how hard you drive your car but i don't usually go over 3000rpm. the best i've ever gotten from a tank is 475kms and that was in the summertime with 95% city driving and 5% highway.

now with the winter here, i'm only getting maybe 400km out of a tank now. i checked the o2 sensor and the machine still says it's good, nothing wrong with the sensor.

any suggestions? or this is just it? i've heard of people getting around 550-600kms a tank and it baffles me how i'm onyl getting 400-475kms.

any advice would be great

 

Without knowing how you drive, (spirited vs. old lady-esque) or how much of your overall driving is highway vs city, it's tough to say what your MPG should be.

But as for the recent drop-off, that is explainable. You mention it being winter, which implies you live somewhere with seasonal changes. Where do you live? Cold weather absolutely affects MPG and brings it down, often significantly.

Additionally, ethanol is often added in winter months, which does not provide as many MPGs as gasoline.

 

with the winter season, gas stations change to a winter blend.
also, with the winter season, the air is colder, which is more dense providing more performance,thus killing mpgs

that short ram might not be the best for MPG as when you're idling, the short ram is sucking up all the hot air from the engine

 

It's odd how your best mpg involves more city than hwy commute. Anyways, where you live plays a big role in determining this too due to flat vs hill roads. IMO fuel injection cleaner every 3 fill ups is an overkill. Just use good premium gas and you should be fine.

I guess what you could do is raise your tire psi to a couple over the recommended specs. Also, you may want to check wheel bearings and brakes for rubbing/sticking calipers.

P.S. Nice to see another Nguyen on the forum!

 

i live in alberta, canada. i've done few testdrives on different tanks of fuel because i wanted to experience the difference it'd make between different types of driving styles. i've driven a full tank with full discipline granny styles, and i've gone another tank just flooring and kicking vtec in. the difference was surprisingly trivial.

the grannystyle tank got 475kms vs the leadfoot style which got 460kms, mind you this was in the summer time.

in alberta, where i live especially, there aren't many highways. maybe 2-3 at most. i commute on city streets to my work and rarely use the freeway. i haven't recorded my mpg on the highway yet since i haven't really travelled to another city in this vehicle yet. (only owned the car for about 7 months now)

i understand my mpg should be dropping in the winter as it should. but my main concern is during the summer days. i don't understand how people can get 600kms to a tank when i'm driving consciously under 3000rpm and only achieve 475kms. =(

lastly, thanks for the warm welcoming. haha been trolling these forums for a while now just never decided to make an account until recently. it's good to know there's some people on here willing to help others out

 

^when you say you've never jumped on the freeway, that explains why you havent achieved the same tank as the others.

you say "city" does that mean lots of stop lights and stop signs? are you idling a lot?

 

ya i'd say so. definately not free flow like people in other cities are doing. 95% city driving...haha and i say 5% highway in terms of going 110km/hr for maybe a few mins a day each day.

 

one thing i do know is honda engines dont like ANY kind of fuel additave it doesnt do anything and honda has said before it can ruin things. all you need to do if always use premium. im guessing you dont since you use additaves regualry. our car is tuned to run the best on the premium grade gas anything less and you will see bad mpgs. and you saying you never take the car aboove 3000rpms is also not good you can get build up of carbon because the cyclenders dont get hot enough. i have on 05 and can squeeze 500 miles out of a tanks with city and highway driving and when i do road trips a tank can do 650 or more depending on conditions. i would say im a 7 out of 10 on driving this car hard. but also if you carry a lot of things in you car lik books if you have a sub or anything that weighs the car down so look at that to. i wouldnt worrie to much about it this cr still gets great gas milage for the performance you get and you do mostly stop and go traffic. if you want good mpgs then go to a prius

 

haha yeah...prius not the way to go for me. i put 91 octane in my car, that's all that's available here in canada. i guess i'll stop using the fuel injection cleaners since they don't do anything. car's pretty empty. nothing i don't need in the car. i guess the mpg i'm getting is accounted for....yay...semi-low mpg...boooo.... haha

 

That could be your problem. The OEM replacement units are Denso or NGK Iridium, NOT platinium.

Denso SKJ20DR-M11

NGK IZFR6K11

Platinium plugs can cause problems in cars they are not designed for. Also, the stock plugs are NOT adjustable. You just replace them when out of range.

 

^^this. what are your avg MPH well in your case OP kmh? if you idle a lot and lots of stop and go...your gas mileage will suffer regardless of what the car's been rated for.

 

i'm not too sure, i don't have a computer to calculate it....lol but the idling makes sense now. every few blocks i stop at a red light. so ya the mpg's accounted for i guess

 

suggestion: after a fuel fill-up take a long drive on a highway (freeway) and then check you MPG or litre's

 

i don't have a computer to calculate it. i usually do it by km's driven then how many litres it takes to fill up. only way i can think is writing down the kms driven then filling up after the drive which should only be a few litres fillup...

 

your trip computer (flip through your MID) tells you the avg speed for the tank along with your L/km. at least it should. so you've been doing your L/km by hand? or the MPGs by hand?

 

Does anyone know if the P2R throttle body spacers help MPG?

 

I am guessing your tsx does not have the trip computer so you have to figure it the old fashion way. Keep a writing pad in the car-when you buy fuel write down the mileage (KM's). Take the car for a highway drive and then on the next fill-up write the KM's driven and how many litres-Then you will know

 

i'm pretty sure all 1G TSX's have a trip computer. then again i could be wrong. all TL's do and so do MDXs.

 

the 04 and 05 tsx's donot have the trip computer-06 and up does. In Canada you can buy a tsx with cloth seats and no sunroof. (Basic)

 

^^thanks. didn't think acura would be cheap about it. interesting.

 

yep .old fashion way, write down my kms and how many liters i fill up the next time haha

 

The ECU tries to maintain various air to fuel ratio's (AFR) based on rpm and engine load.

The ratio is based on mass, not volume.

With colder, denser air, more fuel is needed to achieve the same AFR.

Hot air is less dense, and less fuel is needed to maintain the same AFR.

If the air intake temperature was the only factor that changed by installing the short ram, this would conserve fuel during idling.

The impact is not limited to temperature alone. The short ram is less restrictive than the OEM intake. When the car is moving, there is usually a benefit to having a short ram because the air circulation in the engine bay is good enough to keep temperatures under control and take advantage of the improved flow.

At idle, the intake temperature of the short ram is likely to be higher than with the OEM intake. However, you're comparing a potentially increased (due to better flow) amount of warmer air to a lesser amount of slightly cooler air (with the OEM). The difference is not all that drastic--you would actually need to log some data to make a determination.