When I test drove the 04 TL 6-speed, I felt that the speedometer reading is too fast (actual speed is slower), by the seat-of-pant feeling. I am wondering if any current 04 TL owner has done any checking regarding this. And what is the typical / acceptable % of error.

My wife's '00 Accord EX V6 has an error of about 10% (too fast) on it speedometer reading, and Honda customer representative said it is within the margin of error which, to me, is way too much.

 

it happens on old cars, but new cars?? not so acceptable...

well...the new TL is very solid built and much more like a european ride, so the car is much more stable at high spds, which makes u think the speedo is wrong

i test drove the TL earlier and the car seems very stable even at 100mph and i wasn't quite noticed the spd...and the speedo is correct becoz i redlined at 3rd gear and it's at 105mph~ =)

 

Yes, I agree with you Alvon. I thought I was the only one that noticed this, so I didn't post it. While driving my car home, my dad was driving our accord and I was driving the 2004 TL, we kept in touch with some two way radios. He would tell me what his speed was and my car showed at least 5 km/h faster.

 

I used my Garmin Streetpilot III GPS to calibrate my speedometer as soon as I got my TL. The Garmin has a MPH readout to the tenth of a mile. My car indicating 80 was actually 78, indicating 70 was 68, and indicating 60 was actually 59.

My RL indicates 70 when it is actually going 66, and my wife’s RX is right on the money.

 

FYI - my 93 Volvo speedo is right on, I checked it against the radar speed trap in the neighborhood, not even 1 MPH too fast nor too slow.

Keep in mind that with the error (being too fast) in the speedometer, the warranty miles actually becomes less than 50K, because you accumulate miles faster than it has actually travelled.

 

jime - that error you measured on the TL is very aceptable to me. However, the error on your RL is way off, just like my wife's Accord.

 

Car and Driver said the German cars are even worse, and are consistantly showing faster than actual (I guess it helps those 0-60 numbers for drivers). they never did get an explination from the makers. They had a full article on this. And said that the trip computer, remarkably, was correct, but not the speedo

 

I got this from a friend with a BMW 530. He noticed that his speedometer on the dash always shows speed that is about 7-10%% higher than what is displayed by the trip computer in the "actual speed" section.

He brought that up with his BMW service rep and the rep said that that is normal and the speedometer working as specified. The speedometer on the dash is not supposed to show speed that would be lower than the actual speed, but it is perfectly within the specs for the dash speedometer to display speed that is 5-10%% higher than the actual. The trip computer is the only one that is aware of the actual (and the most accurate) speed, but that speed is not normally displayed to the user. That is what the BMW technician said. Go figure! I'm not sure if Acura is the same.

 

I heard my Acura technician told me this 4 years ago. He said it's for your safety. The law seems to only regulate the odometer should be precise, and speedometer shouldn't be over/under the certain percentage... for exmaple, I saw NY inspection station does the speed/emission test, they have to put the sensor above your dashboard or hood and test your emission at some range of speed. If you try to run low to have less exhaust, I guess it will signal that your speedometer is not correct...?

 

Speedometers aren't directly tied to odometers these days. With the proper size tires, the odometers in essentially all cars are very close to correct. Speedometers can vary. Unless your error is more than typically 5 mph at highway speed, it will be considered "normal" for warranty purposes.

Personally, I'd rather have the thing be right on, rather than have it trying to protect me, trying to trick me into driving slower.

 

My TL speedo reads about 1 mph fast....I think the tach is dead on, but because of the angle from your eye to the dial at, say, what looks like 2000 from a driving position is actually a little higher, maybe 100 rpm if you get your eye down to the level of the tach...hard to do when driving. In any case 60mph should take 60 seconds for one mile and the tach should be just under 2100, and I am sure that the 030s and EL42s are not precisely the same rolling circumference, so the rpm at a given speed could be slightly different. Another thing, if you use mileposts on the interstate to do your calibrating, use a bunch, because sometimes they are not accurately placed. The ones that also do 1/10s probably are more reliable.

 

Pretty much every modern car displays a speed faster than is actually correct. I've checked this with assorted handheld GPS receivers, and you can check it yourself in any car with a trip computer (set cruise control on a flat road, and reset the trip computer).

My 01.5 Passat would consistently read about 4-5 mph faster than it was actually doing. This may confirm previous comments about German cars. When I queried it with VW, they said it was a safety feature -- and stopped you getting tickets. I've since checked it with assorted rentals and although the amount of inaccuracy varies, every one of them has shown a speed higher than actual.

 

Further to my last post about car and driver, here are some facts from it:

Variations in tire size and inflation levels are the sources of error these days. Normal wear and underinflation reduce the diameter of the tire, causing it to spin faster and produce an artificially high reading. From full tread depth to baldness, speeds can vary by up to about two percent, or 1.4 mph at 70 mph. Lowering tire pressure 5 psi, or carrying a heavy load on the drive axle, can result in about half that difference. Overinflation or oversize tires slow down the speedometer. All our speed measurements were made on cars with new stock tires correctly inflated, but one might expect a manufacturer to account for wear and to bias the speed a bit low; results suggest that not to be the case.

So we sought out the rule book to find out just how much accuracy is mandated. In the U.S., manufacturers voluntarily follow the standard set by the Society of Automotive Engineers, J1226, which is pretty lax. To begin with, manufacturers are afforded the latitude to aim for within plus-or-minus two percent of absolute accuracy or to introduce bias to read high on a sliding scale of from minus-one to plus-three percent at low speeds to zero to plus-four percent above 55 mph. And those percentages are not of actual speed but rather a percentage of the total speed range indicated on the dial. So the four-percent allowable range on an 85-mph speedometer is 3.4 mph, and the acceptable range on a 150-mph speedometer is 6.0 mph.


Here is the link to the article: http://www.caranddriver.com/article....&page_number=1

Enjoy reading it, it has a lot more info!

 

When my handheld Garmin showed 100k/hr, my 2000 TL speedo would display 110.
When I tried the same same thing on my 2003 TL, the speedo display was more like 102km/hr
My 2004 seems more similar to the 2003 TL ie more accurate(although Ive only tested it once).

 

In 1998 I went through a whole summer of issues with my '98 Integra GS-R speedo reading 9.5% high. The service department hooked up their 'computer' to the car and went for a ride and verified that the speedo was reading fast (apparently the computer does know the accurate speed). The 9.5% was within Honda's 10% and therefore, they would do nothing. They ultimately created a grid for me to carry with me so I knew exactly how fast I was going.

The district rep told me (I demanded a meeting with him) that Honda's policy is to set them fast, but they vary from batch to batch (which i find hard to believe). He said that by setting them fast, they elimiate their risk of people sueing them for getting a speeding tix and claiming the speedo was off. I told him that I was going to go to a larger city and get a ticket for driving slower than the minimum posted speed and sue them. He had nothing to say other than Acura was doing nothing with the speedo.

My '03 CLS6 seems to be fairly close .. but have no idea for sure. I use it as a guideline and being an Acura owner for almost 6 years, i just go along with traffic.

 

Sorry guys the garmin or any civilian GPS device is not nearly accurate enough to calibrate a speedometer. The only devices with this accuracy are the fith wheel or laser equivalent which measure distance and time on the ground. I haven't done it myself but in the police "your speed" radar devices it has always been right on.

 

In the long run, our cars will show more miles on the odometer than the car really traveled. Not good for resale, or does it really even affect it that much?

 

vtechbrain,

I disagree about your opinion of what it takes to "calibrate" a speedometer. We are not talking about 100’ths of a second accuracy provided by a 5th wheel instrument.

Yes, my Garmin Streetpilot will jump plus or minus 0.2 mph as it continually changes from one satellite station to another, but even 0.5 mph accuracy is better than you can read on the TL speedometer.

 

The garmin's acuracy is at best within 10 meters. I'm not implying its useless, Its just not the most precise measurement available, a third wheel is. When your talking of variations of +/- 2% the garmins accuracy will not be enough to figure it out.

 

Our odometer should be accurate. As long as you don't mess up your tires.

 

Its interesting you said that about the faster speed. I noticed it on distance.
I have been driving to work the same way for years, in many different cars. I know when I go by a certain house, I travel exactly 20 miles + or - .1mile... My 04 TL showed 20.7 miles when I get to the same house. Thats a 3.5% error.

 

My wife's '00 Accord EX V6 has stock rims and tires (and 35 psi tire pressure), and the speed is definitely ~10% too fast. The odometer is also wrong (high) compare to my Volvo.

I am glad that the '04 TL has relatively smaller errors.