I just got an '08 tl. It is my first car and it is fantastic. I really don't know much about cars and I have some questions. I've been checking on the Trip Computer and I got about 18-20MPG when I first started driving it. Lately, I have been getting around 16 max. Could it be the tire pressure? When I first got the car, it was around 29/30-31. I saw the warning on the screen and filled it. I read that you're supposed to read the tires cold, but I get different readings depending on the temperature. I can get readings like 32/31 or 34/33. Manual says 33/32, but I can't seem to get it right. Was having it at 29/31 giving me better gas mileage?

I've only filled the tank with regular so far. I don't know what was in it before I drove it off the lot. My tank is getting low and was wondering if I should keep it on regular or run it empty and splurge on better fuel?

I also heard from a mechanic at the acura dealer that I should wax my car after every wash or else the black will fade into a grey color. It was by 3m but I forgot the name of it. Anyone know what it is? I haven't wash it yet and it is starting to look grimey. When I want to wash it, rain is not too far away so I wait and keep putting it off. I'm just new guy looking for some input. Appreciate any help. Thank you.

 

The TL requires premium fuel. That's probably at least part of your fuel economy issue.

 

Really? When I asked the manager at the dealership, he said regular is fine. When my brother had an 03 tl all he did was put in regular, but he was a cheapskate though. Sorry, but premium is what now? The next step up or the highest? As you can see, I don't know squat.

 

Mechanic/Detailer/Firefighter/Sales Rep/Professional Racecar Driver/etc

OP, you do not have to wax your car after every wash. I waxed mine every few months. Your paint will not turn grey

 

Premium is going to be your highest grade. Octane rating depends on your altitude a bit, but here it's 91. The manager is a moron. Says right in the manual that it's required. Sure it'll run, but it'll be fighting the knock sensor the whole time. It should even say it inside the fuel door.

 

Run 91+ octane, 93 when available

 

I was just going by what he's seen in his line of work at the dealership.

Ok, so premium seems to be about .24 cents more expensive than regular at the moment. I guess I should just pay the extra $4-5 on a full tank? I have a couple notches left on the fuel gauge. Do I wait til the light comes on than fill it or just fill it whenever?

Is there an edit button around here? I can't seem to find it.
Anyways, I forgot to ask what would happen if I kept using regular fuel? Aside from less gas mileage, anything else?

 

Edit button is right bottom corner of your post, to the left of the Thanks button, but I believe it is only there for 15 min. I would just pay the extra for the higher octane fuel for better performance/mileage. I really don't know all the side effects to using regular, but someone more knowledgeable will hopefully chime in on that. Welcome to ACURAZINE!

 

Thank you for the welcome. I am digging this place so far. Getting a lot of help quickly.

I tried to edit my post in under 3 mins and I couldn't see the edit button. Just see 'quote, multi quote and quick reply.'

 

It's prolly because you havent been a member atleast 15days and/or you dont have 5 posts (which you do already).

Here's what I learned. Cars these days can pull or retard the timing depending on many factors INCLUDING the octane for gas. It's OK to use a lower octane fuel (IF YOU HAVE TO) if your car RECOMMENDS 91+ (though IMO it's better to stick with whats recommended/required). Now if it says 91+ REQUIRED then stick with that. There's a reason it says REQUIRED. If you use what you're suppose to, the car will run the way it was engineered to, PLUS you get the MPGs and power you're supposed to. Using a lower octane fuel CAN (not always) cause damage to your car, besides to your wallet at the pump. lol Using regular (87) even though it's cheaper will costs you more than using premium (91+) even though it's .24 cents more (like you said it's just $4-5 more), because your getting less MPG and staying at the pump more. And somebody correct me if im wrong, the motor in the TL is has a high compression ratio of like 11:1 right? Remember: Using a lower octane fuel can/will reduce performance, not just MPGs. I've read plenty of regular vs premium threads on here an online. Some says there's no difference, and other's say it is. You have to thing of it long-term. How do you want your car to run when it hits 100K, 150K, and even 200K miles.

Hmm... for comparison I like to explain it like this. Say you have a bad spark plug and it's causing a misfire. Since the fuel is not being burnt "efficiently" for that cylinder, you're just blowing the rest out the tailpipe and with today's prices you want your car to be as efficient as possible. Using lower octane fuel regularly can (it happened to me on my last car, plus it ran a little rich, plus I had a temporary misfire) harm your cats. Catalytic converters aren't cheap and you can throw an emissions code. I havent seen it in an acura as of yet. I'd start out small like resetting your average mph/mpg, filling up with premium, checking tire pressure, checking your air filter an etc.

 

Inflate your tires to the proper size or at least very close to it. next as said already use 91 or better. try to use a top tier gas as well like Shell. I use only shell 93 in all my cars. Next don't let the car go down to where the light comes on reason being the dirt and other contaminents in the gas will get sucked up into your injectors and clog them up thus resulting in poor performance as well. I usually fill up when I'm down to 1/4 tank but that's me just being me. Also check the air filter it could be dirty too and need to be changed. Something you can do yourself just to let you know. Don't let the dealers talk you into anything that's their job at the end of the day, to get you to spend money with them for nonsense.

 

if you were driving a 1995 integra than you can put regular gas in it.

but your in a 2008 tl, please show your entry-level 'luxury sport' sedan some love!

 

Yeah fill up with Premium octane gas. It should say premium gas only. I'm also having issues with gas mileage but i fill up with premium gas? :/

 

Always measure the tire pressure when the tires are COLD, i.e. have not been driven on for more than 1/2 mile in the prior 8 hours.
Check the TPMS readings after you've just started driving the car in the morning-- use 33/32 as a minimum; you'll get worse MPG at lower pressures.

Tire pressures can be varied for preferences, i.e. I run 37/34 or 36/33. Just don't exceed 40 psi on stock-size tires and keep the F/R pressure differential and you'll be fine.

Don't bother with the tire pressure or TPMS readings after driving more than a mile-- the tires heat up and cause the pressure readings to increase.

Welcome to AZ.

 

Welcome to Acurazine Burntrat. It sounds like the mechanic is REALLY leading you astray. Do not wax your car be a few times a year. The guys are right about the premium fuel. If anything else sounds weird (from your mechanic), just ask here. We can set things straight for you.

 

I'm like on the last notch of the fuel gauge. Should I wait till the light comes to drain most of the regular or just fill it asap with premium?

I try to read the tires when it hasn't been driven, but didn't temp give me different readings like before I leave work when it's cooler and after work when the temp is warmer. Which do I go with? 40-50 degrees or 60-70 degrees?

 

Yeah just wait til the light comes on and fill er' up with premium. Also you have a 3 gallon reserve gas tank just letting you know. (correct me if i'm wrong please)

 

Do the pressure readings and pressure adjustments in the morning, when the air temp is lowest.

 

We have a reserve gas tank

 

Just got it filled with premium at sunoco. There was an Ultra Octane I think. Am I not ready for that and just stick with premium? From the (light on) empty to full, I filled about 12.xx gallons. I thought it was supposed to be more so I forced it like 3-5 times to 13.xx gallons. Is that ok? It felt like I could keep filling it drop by drop. All in all, paid about $47, less than I originally thought.

 

I think what he was trying to say is that you have ~3 gals left when the gas light comes on.

 

I missed this post, or i would've multi-quote with my last reply.Premiums 91+ is fine. Never try to squeeze in extra gas. It can damage the charcoal canistor. I doubt that little bit will harm anything, but I see people do that a lot. It's not good to force in gas an there's other reasons not to do it, besides it spilling down the side of the car. I know someone else can give you more details on why it's bad to do this.

 

yep same situation, this 08 tl type-s is my first car, im just starting and want to continue in the industry.
i too also used reg fuel at first but later realized it required premium unleaded (there goes a couple bucks :P)
so far this forums great for info especially for new guys like us so jus be patient ull learn everything soon enough

 

Yeah when you hit E completely you have a reserve gas of 3 gallons. lol correct me if I'm wrong

 

Someone did the math in a thread here and figured out that, due to the better MPG from using premium, we would actually be using more money by filling with regular instead of premium, so premium saves you $ in the long term.

Welcome to AZ.
Actually, about 3 gallons remains in the tank when the "low fuel" light activates. The needle on the fuel gauge is still above the "E" at that point.
IDK how much is left in the tank when the needle drops all the way below the "E"...

 

Can you link me to that thread? I am curious to see how much more I would save.

I appreciate all the help everyone.

Oh, there is a like a leash for the gas cap. Where do I connect it to? I can't seem to find it in the manual. I thought it put it in the right place, but it fell right off a second later.

 

A leash? Please explain? is it the one that has the ball end or the thing that connects it from the car to the cap?

 

It's like a wire that connects the cap to the car. I just don't know where to place it. On the end is like a ball with like 4 prongs around it.

 

See post #24 for a photo in: https://acurazine.com/forums/3g-tl-2004-2008-93/gas-cap-holder-565674/.

 

Hmmmmm.... I thought that's where I originally put it. I'll try again next fill up. I don't remember having that other attachment point to the lid.

Also, after filling with premium, I'm starting to get even worse mileage. I resetted, and am now getting 15 mpg city. Maybe I am just driving more aggressive now. I don't know. It does feel like I can accelerate quicker with the premium though.

 

Welcome to the club! You'll learn alot being around here. Everyone for the most part is pretty knowledgable.

Congrats on the 08 TL BTW...great choice in a vehicle!

 

Appreciate the welcome everyone. I'm learning quite a bit already. Yeah, TL's are real nice. I fell in love with the TL 3G as soon I saw it. Took me a while to get it, but it was worth the wait.

Only thing that would make this car close to perfection is if I got more gas mileage out of it. I just checked the engine air filter and cabin air filter. Both seem to be pretty much new. It is a CPO car which I had for less than a month. I just filled the tires to 34/33. I know it's 33/32, but I figure it'll go down soon anyway. I just switched to premium fuel. Is there anything else that I am missing that is causing me to get 15MPG in the city? I was so happy at first when I got 18-20MPG. I am going to go to granny mode for a week and see if that improves it or not.

 

^ If you have a lead foot, your MPG will be much worse. I had read that if you're approaching a red light, don't put your car into neutral if you have a MT. Just let the engine come close to idle as possible and then put it into neutral and press the brake. Granny mode will definitely help but if you have a lot of red lights to contend with, it won't help you in your situation.

 

Good that you are using Premium now. No need to wax your car every other car wash unless you wash your car once every 3 months.

Go back to that dealership one last time to tell the manager and mechanic to read the f**king manual.

I also recommend that you calculate your mileage and not rely on the computer. Mileage / Gallons. What is your driving habits like? Mostly city or highway?

For reference I have an 08 TL as well and I drive 80/20 Highway/City. I average between 26-28 mpg and my trip computer is always 1-2 mpg higher.

 

Tire pressure
The most accurate reading you're going to get is in the morning. Your car should be in a garage or under cover or if in a driveway, not exposed to sunlight (that raises tire temperature and pressure). Use a high quality gauge when checking your tires and fill them to the recommended pressure on the placard. If a tire reads 28 pounds and it is suppose to be set to 32, when you drive to a place to fill it, just add 4 pounds and you'll be fine.

Checking fuel mileage
The absolute best way to check your mileage is to fill up with quality fuel at a reputable station (with good in-ground tanks), and then do your re-fill at the end of your mileage check at the same station and pump and in the same manner (to the point of auto shutoff). Then divide the gallons burned into the miles driven for the results.

Fuel tank level
You should avoid letting your fuel tank go below the halfway point if possible, especially if you live in an area that has wide temperature swings between day and night. The reason for this is to minimize the buildup of condensation in the tank which can adversely affect performance, mileage, and can lead to other problems.

Premium vs regular fuel
Our engines were designed to burn premium fuel with an octane rating of at least 91. You'll note that the filler door states, "Premium unleaded fuel only". Using regular grade fuel, which has an octane rating of 87, will return lower fuel mileage but far more important than that is what potentially you can do to your engine by using regular gas. The ECU will retard ignition timing which will be accompanied by a change in the fuel delivery to the cylinders. However, the real danger lies in the potential of detonation.

Regular fuel is more prone to sudden ignition under high compression (mechanical and that caused by an expanding flame front) than is premium and can suddenly detonate (explode) rather than deliver a controlled burn. If this happens major engine damage can result. So using regular fuel in an engine which is design to burn premium fuel is courting disaster... do so at your own risk.


I would add that if you are worried and concerned about fuel economy, perhaps you should have done some more research before buying a performance sedan. Fuel economy is not a primary concern with these cars since they were designed to delivery a measure of performance to their owners. This is in no way meant to be a flame so please don't take it that way.

For the record, I own two 3G TL's. Mine is an '04 manual and my wife's is an '05 automatic. Both deliver quite acceptable fuel mileage both in town and on the road. However for us, in town can equate to congested suburbs or a small city, not something like Chicago or New York by any means.

Take your time, read through as many threads on these forums as you can to gain insight and information, and please do continue to ask questions. We are here to help you along as much as we can.

 

I run my tires at 34 cold with Nitrogen. It will go up to 36 when hot. It does help a bit with MPG but helps a lot with flat spotting.

 

You have to give the ECU time to adjust to the premuim full and your driving habits. You might try an ECU reset and go from there.

https://acurazine.com/forums/showthr...&highlight=ECU

 

I didn't have a lead foot at first, but I'm catching myself driving a little bit faster and faster every week. I'm AT, would that still apply or is that bad for the tranny?

I still haven't washed or waxed it yet. Seems like rain delays it for me. I still need to get some cleaners, towels, etc. Also need to get something to remove scratches. NBP shows like every flaw. I really didn't notice it when looking at it at night, but the day after I buy it, BAM. Noticed a lot of scratches and someone from work dinged my door.
I've been driving in the city for 97% of the time. Lots of stop signs, lights on the way to work. I should probably find a better route. I am amazed at you getting 80 MPG on the highway. I'll have to remember to reset my distance after I fill up and then keep track of how much I fill up the 2nd time. My forgetful mind won't remeber though.

Thanks for the tips. I wasn't really looking at the TL for best fuel economy, but 18 city seemed decent to me. I was mainly looking at the TL for looks and reliability (not sure now, but does the newer TL's still have tranny problems like the 2G?).

Nitrogen? Can I get that at my local gas stop?

 

Yeah, I was just reading through the thread about resetting ecu. Looked like most of them noticed a difference in performance, but some of them mentioned that the MPG dropped. That is the only thing really stopping me from doing it now.

 

I didn't mean 80 MPG. It meant that 80% of my driving is highway, 20 % is city. 80/20.

Look into different tire shops. I'm sure someone does it in your area. It's not essential but what I noticed is that with air the pressure will range from 32-39 while with N2 it ranges from 33-36. It's more stable.