Rbadshaw413

Okay so I just had a new gauge insert installed into my 01 GT. Looks great and everything seems fine except now the speedo is off by what looks to be about 8 0r 9 mph. I had already taken it back to the shop once when they first installed the insert because it was about 15 off. So im not exactly wild about going back up there. What can I do to check it myself?

defconfire

does it read high or low?

Rbadshaw413

Reads high...

defconfire

do you happen to have 4.10 gears?

Rbadshaw413

No...just the stock 3.23s

TX97GT

if you took off the needles to install the insert, don't you have to put them in the exact same spot on the center pin..?
And don't push them down too far

Rbadshaw413

I didnt see exactly how they did it, but Im pretty positive the needles had to come off. So would I have to take the dash back apart to check them?

Eagle2000GT

It took forever for me to find the cause but my speedometer is off exactly 7 mph. It reads faster than I'm actually going. The reason is that when the previous owner put custom gages in he didn't get the needle back in the right place. If you look at your speedometer carefully you will notice that it doesn't go to zero. If you put the needles back on at a dead stop you will read about 7 mph off. To set the speedometer needle you have to jack up the car and have the wheels turning. (I have heard of people driving down the road and putting the needle on but I don't recommend it.) You then use your odometer to read your correct speed and place the needle at that speed.

I have the procedure written down at home, but to use the odometer as a speedometer you have to hold the button down when you turn on the key to get into troubleshooting mode. After it goes through a self test you then press the button repeatedly until you get to ENG (English). The odometer will now display your speed.

Edit: Don't do what I did. Because the speedometer was off the tuners thought I had either 3.73 or 3.55 gears (I jacked up the car and checked by rotating the tires. I have 3.27 gears).They tried to set the speedometer using the computer.If it was setfor 3.73 gears the odometer read 17% fewer miles than actually traveled. It is now set for 3.55 gears and the odometer reads 8.5% fewer miles than actually traveled and the speedometer still now 2-3 mph off. Now I have to not only fix the needle but take it back to the tuners to have it set for 3.27 gears.