Hi Everyone, Just picked up a CPO '08 TSX (~90,000 km) yesterday. Drove it around, combination of city and highway speed, and was not impressed to see that my 100km or so of driving took out a quarter of the tank of gas. Also got out of the car when it was idling and the exhaust smelled somewhat like gas, so I assumed it was running rich. Surprising thing is, the onboard efficiency indicator says I'm using less than 10L/100KM, and that my now 75% tank has another 500km left . Unless the fuel gauge is wildly inaccurate, can't see that happening. Was wondering whether anyone knew how the onboard computer calculates the fuel efficiency? Is it based on how much fuel is being injected into the engine? If that's the case, I seem to be running even better than the advertised 10.9L/100KM, but this seems to go against the quarter tank of gas that I've used so far. As well, don't know if this is relevant but I noticed that clear/whitish steam comes out from my exhaust. I've been seeing these on other cars on the road and just assumed it was normal. My knowledge of cars doesn't really extend past checking fluid levels (checked this morning and they're all normal) and whatever I've read on forums, so any help/guidance/pointers would be appreciated. Thanks!

 

Don't know about the computer calculations, but mine has always been about 10% optimistic compared to the real consumption (so 30mpg displayed is really closer to an actual 27mpg), though acurate as far as miles left until empty. And even at 145k miles on my 04 6sp manual, I can still go about 500 miles on a tank of gas if I drive nicely and definitely above 400 miles under pretty much any circumstances. Usually the gauge shows half way right around 250 miles and if you fill completely up (which is tricky in this car), you probably shouldn't even see a drop from full until you are past 75 miles or more.

So it could be your gauge. I guess the only way to know is to carry an extra 5 gallons in a can and run your car until it runs out of fuel. Then you'll know if it's the gauge or the car... Good luck.

 

I noticed my 08 TSX fuel gauge works differently than in 03 Accord 4cyl I drove before (they are pretty similar vehicles with the same fuel tank volume). In Accord gauge arrow moved slightly only after I drove 50 miles or so, than showed half tank at exactly 200 miles, but after that went down rapidly and fuel light came on at ~310 miles.
With TSX, an arrow moves down rapidly and constantly from the beginning and shows ~170-180 at a half tank mark. Then it slows down and a light come on at 300-310.
Average mpg for Accord was pretty constant around 24-25mpg, TSX gives me 23-26 with same commute route and it very depends on how I drive. Also it is always ~1mpg lower than MID numbers. I always use Premium in TSX.

 

What you describe sounds pretty normal for the TSX. First of all, remember that calculating mileage the old fashion way (dividing miles traveled by the amount of fuel you add to the tank) is pretty inefficient. You never really know if what you add this time fills the tank to the same level you did the last time. Pump efficiency, atmospheric differences, temperature, all have a bearing on how much you can jam in. That said, some feel that the Acura fuel usage computer is not accurate. Can you ever really know which is the better way to track your mileage?

The gas gauge does have kind of a mind of its' own, but so what? It should read full when you fill it, and when the low fuel light goes on, you'll have about 4.5 gallons left in the tank. That's really about all it needs to tell me. So the 17.1 gallon tank still has about 9 gallons left in it when the gauge is showing half full. I don't find that to be a problem. In my experience, all fuel gauges take some getting used to. The TSX has been no different. The white vapor escaping from your exhaust is just steam and of no concern. Once everything comes up to full operating temperature, it will disappear (unless it's like -20 degrees).

 

thanks for all the input! I guess I'll drive it a bit longer and see how it turns out. Couple more things to note, I started it today after having parked it for 4 days or so (I take transit to work) and it felt like it was slow to start, took about 6 cranks before the engine fired (it's only around -2C where I am right now). As well the exahust smell inside the car was terrible once it started. I drove it out of the garage, turned it off and back on a few min later and the smell was fine. Don't know if any of you have encountered these issues? Anyways, thanks again for your replies - really appreciate it.