Rileydawg

Hi all, I am new here. A member in my family just bought a 05 TL with 150,000 miles on it in very clean condition. She told me that it doesn't have very much power and I was rather surprised as I have two friends that have owned these cars. She also told me that she was using regular gas in the car and I thought that this might be the problem. Upon refilling it with premium, the situation has not changed, Any ideas on what to look for would be greatly appreciated!

Thank You

horseshoez

iTrader: (2)

How is the fuel economy?

Rileydawg

Do you not know I will check

El_Cheapo

- How does it idle?
- How does it crank when cold?
- Has it been smogged recently?

Several things can cause low performance. I would start with these:

- Dirty throttle body and air filter
- Low fuel pressure
- Clogged cat

horseshoez

iTrader: (2)

Funny thing, I've never seen an air filter cause poor performance. Per the EPA study done on air filters done a few years back, unless the filter is so clogged you can barely start the car, the performance hit will not be terribly obvious.

El_Cheapo

Agreed. I have yet to see an air filter itself be the cause, but you would be surprised what people do to their cars.

Turbonut

iTrader: (1)

How much premium did you put in the car, and many miles since the premium has been added?

horseshoez

iTrader: (2)

Premium versus Regular is not the issue. There have been several times since I bought my car I've experimented with Regular and there is zero precipitable difference in both performance and fuel economy.

Jackass

I know this has been beat to death, but I really think this is vehicle specific. Mine suffers with 87 octane and perks up quite a bit when I find 93 octane. Do I think 87 will hurt my car? No. Is there a performance difference and/or mileage difference? Yes...not huge, but there is a difference.

Now to the OP, if they have always used craptacular 87 octane, it could have fuel delivery issues. No idea how much detergent was in the 87 they were always using. At this point, it could be many things without knowing more details of the behavior.

horseshoez

iTrader: (2)

Interesting, in my case, my two very best tanks of fuel from an economy perspective, was when running Regular (87 AKI); both tanks yielded well over 500 miles with the fuel economy numbers in the 35 to 36 mpg range.

Turbonut

iTrader: (1)

Since purchase, 2004 A/T, and for the last 14 years have always used Premium, but in January this year thought I'd switch to Costco regular, why pay the extra. There have been numerous threads on the subject and they have said no difference, in fact nfnsquared (6M/T) even mentioned he saw no timing being pulled while using Regular, and no problems while on a steady diet of Regular.

Now, I very rarely drive the car and the wife only drives it maybe 300 miles p/month, so first tankful no problem, second tankful same, however she really couldn't recall if any heavy acceleration was needed, but on the third tankful she comes home and says something wrong with the car as it lacks pick up, but no missing, idles and drives fine except under heavy acceleration. Take it out and give it a try, yup, rpm's climb, but it's like pulling a 10,000# trailer, so shut it down @ 4500 rpm. Everything perfect on the car, so can it be the gas...............Let's find out. Had her drive the car, then I filled with Costco Premium, 17.1 gal. Drove it 150 miles and gave it a try, back to old self "flew" up to redline, so Premium makes a world of difference and there is no argument about that, at least for the A/T, so if you guys with a 6 M/T don't notice a difference, hard to believe, so be it.

Before some think, what does a woman know about cars, let me say something about the wife, she's a true gear head and probably knows more than most guys, comes from a family of motorcycle racing, drag racing, modified stocks, in fact she was the person that discovered the trailing plugs not firing on the rotary and ended up getting it bought back and we purchased the redesigned year at Mazda cost, saved us $8,500.

horseshoez

iTrader: (2)

Interesting. Last fall I drove from New Hamster to my son's place in Denver with the car loaded to the gills with stuff as well as a big cargo bag and mountain bike on the top of the car; as an experiment, I drove the entire 3,200+ miles running on Regular fuel and never once noticed any lack of power or a drop in fuel economy (errr, well, on the way out with all of the crap on the top of the car my fuel economy sucked, but that was expected).

Jackass

Again...I think many of us have validated that there are different experiences with 87 vs 91 over the many years we have beat this theory up. Lots and lots and lots and lots of people have confirmed they have no issues with 87 octane. There is for sure a group of us that have noticed differences. One or two cars is not a proper sampling size by any means. Even the fuel blend that is available in NH may be quite a bit different than the blend I get in MO. The condition of our engines or plugs could be different.

So before this continues to be a 87 vs 91 battle....lets summarize:
- many have tested 87 out and have no complaints/issues
- there are some who have had issues with 87 and chose to stay on 89, 91, or 93
- when in doubt, go up to 91 to see if behavior changes...if it doesn't...go back down to 87

There are two main risks of 87:
- knock, which should be dealt with by the knock sensor and ECU
- lack of detergents, although any 87 in the US should meet the same bare minimum which is "more than likely" enough
- many 91 fuels have additional detergents that "claim" to be better (top tier rated 87 should have the same as the premium)
- the amount of detergents is not clear how much is fact, science, or marketing

If 87 works for you, awesome...use it. If it doesn't, figure out if 89 or 91 is what you need to get to a happy place. My happy place is HyVee 91 octane since it is Ethanol Free. 87 octane in MO is mandated at E10. If not HyVee, then it is usually Costco or QT 91 but it is E10. Not always easy to find Ethanol Free around here.

horseshoez

iTrader: (2)

Here in New Hampshire all fuels are E10, E15 (really rare), and E85 (also very rare). Regarding the 4,300 mile trip I took last November, I traveled through a total of 12 states and used 87 AKI E10 for every tank except the very first, which was 93 AKI E10, and is my usual fuel.

Rileydawg

The car in question I will not see until next week when I can take a closer look and drive it. I did tell her to keep premium gas in it.

Turbonut

iTrader: (1)

HH-If you get a chance, do a 3rd gear pull.
With whatever fuel you've had in the car for a while, 3rd gear @ 40 mph, hit it hard and check the time to 70 mph.
Then after a couple fill-ups of the opposite grade try again and see if results differ.

Rileydawg

Found out that the car did have a smog test. I will drive the car next week when I see her.

losiglow

iTrader: (1)

Here's my laundry list of stuff I do with a used car - buy an OBDII bluetooth reader and download the TORQUE app to see what the LTFT is at (long-term fuel trim). If it's more than +/- 5%, there could be problems anywhere from vacuum leaks to crappy spark plugs to bad/dirty sensors to injector problems. Tune everything up. Anytime I get a new (used....) car, the first thing I do is tune it up. New plugs, clean sensors and coil pack contacts with CRC electrical cleaner, ATF 3x3 "flush", good synthetic oil change, air and cabin filter. Get a $20 boroscope on Amazon and remove the upstream A/F sensors (O2) and inspect the catalytic converters to make sure they're not clogged. Do the same to the cylinders to make sure there's not a ton of carbon buildup. Have the battery and alternator tested at an auto parts store. It's free. Put in a fresh tank of top-tier premium.

csmeance

she probably has a ripped air intake boot (looks like a accordion) that's letting unmetered air into the engine... Common issue after so many years with plastic breaking.

Rileydawg

Seems like a smog test would have caught that?

csmeance

most of the time the car won't throw a CEL and the exhaust will test fine. Only looking at the underside of the pipe can show if it's cracked or not:

Rileydawg

Thanks, I will have her check that.

horseshoez

iTrader: (2)

Correct me if I'm wrong, but isn't the air intake boot upstream of the throttle body? If so, then there will be no unmetered air entering the engine.

05 Acura TL

These cars use a MAP, so any air pre-throttle body is still metered air, if these cars used a MAF sensor then this would be correct is air was getting in post MAF aka tear in the intake tube after the sensor.

That is correct, the 04-08 TL's use a MAP, so as long as the air is pre-throttle body it won't affect anything, except unfiltered air if its post air filter. Now if its post throttle body, then you will have issues, since that would be a vacuum leak at that point.

However I have seen cars have issues with tears in the intake boots with fuel economy and feeling a bit sluggish. Could be something to look into as in this situation just incase.

I am not sure how long she has had the car, but if she does a lot of low speed city driving for extended periods of time and since its getting hotter out for most states, she might be experiencing some "heat soak", usually goes away once you pick up some speed (highway driving for a bit).

horseshoez

iTrader: (2)

Agreed.

losiglow

iTrader: (1)

Probably from sucking in hot air from the engine compartment.

My '09 Pilot had the boot tear. Purchased a used one online and replaced it. Never made any noticeable difference but at least dirty air wasn't getting in any longer.