Speedometer is off

[HangLoose]

Well first I'd like to thank everyone whose been replying to my threads, its been helping me a ton getting my car up to par so I can mod it up!

Recently I tested how far off my speedo is, its off around 10-12 mph. This isn't a problem but its extremely annoying.

What could cause this? I tested it with another car, only thing thing different is 2003 GTS rims but tire size is 215.

 

[bryanwheat]

If you have a different diameter tire than it will throw the speedometer off. The 215 is the width of the tire. What is the second number on the tire, and what size rim?

 

[HangLoose]

215/50/17 is the size

 

[bryanwheat]

That tire is a larger diameter than what came on the car stock. The stock tire was around 24.9 inches in diameter, the tires that you have now are around 25.5 . This will make the speedometer read lower than what you are actually going. The closest size with a 215mm wide tire on a 17 in inch rim would me a 215/45/17 which would be 24.7 inches in diameter.

 

[HangLoose]

But, that's not the case, the speedometer is going faster than what I'm actually going, its anywhere from 10-12 MPH off, like when I'm going 65-70 on the speedo, I'm actually going around 55.

 

[bryanwheat]

But, that's not the case, the speedometer is going faster than what I'm actually going, its anywhere from 10-12 MPH off, like when I'm going 65-70 on the speedo, I'm actually going around 55.

Someone could of pulled the needle off at one time and re-installed it wrong. Does the car have aftermarket gauge faces?

 

[HangLoose]

no, ive never seen a car do this before honestly

if i can adjust the needle ill jsut do that.

 

[bryanwheat]

no, ive never seen a car do this before honestly

if i can adjust the needle ill jsut do that.

You can adjust the needle, but it is a little bit dangerous to do because you will be driving the car while doing it. The way that I've done it in the past is to remove the cluster, pull the clear plastic cover off the front, than reinstall the cluster. From there pull the needle off of the speedometer and go for a drive. You will need another person to follow and pace you. Have them drive at say 40 mph than while you are going 40 push the needle back on pointed at 40.

 

[HangLoose]

thank you so much!

 

[daboss5150]

maybe someone can help me. Ive got a 97 eclipse rs w/turbo and my speedometer reads double 30 means im going abt 15, 80 means im going abt 35, and 130 means im doing abt 70. Ive heard several guesses on what i should do. How do i fix this the right way. thanx