I have a 94 ES300 and my speedometer says that I'm going about 5mph slower than I'm actually going. Is there anyway to fix this?
I did replace the needles about a year ago. Can the MPH and RPM needles be interchanged? (That's the only thing I could think of that might be causing the problem).

 

bigger wheels and tires throw your speedo off. but since you said you changed the needles, you need to mess around with them to get it back where it needs to be. where is the speedo needle when the car isnt moving?

 

Has the speedo been not reading correctly since you did the needles a year ago, or did it start reading incorrectly more recently than that?
The speedo and tach needles should be interchangeable. You should be able to just take the needle off and put it on again at the right spot.

 

The speedometer needle is below the zero when the car isn't moving. I'd say a little less than 1/2 an inch below.


I'm not sure what you mean by taking it off and putting it in the right spot. I mean ... since it's weighted, won't it just rest where it wants after I put it on?
When I replaced them a year ago, I put the speedometer needle where it rested at zero, but it would just sink below the zero as soon as I let go of the needle.

 

It sounds like you have a counter-balance problem. I had the same thing happen. It all depends on the placement of the resistors, wire, LED inside the needle. If the weight tends to be more towards the tip, then the needle will want to drop (gravity) rather than staying stationary. Here is what I did to counteract the forces of gravity:

I took the speedo needle off again and, using my soldering iron and a bit of solder wire, I melted a tiny (and I mean TINY!) bit of solder onto the metal counterweight at the base of the needle. Then I put the needle back onto the gauge and tested where it sat. It was still a little below the "0 MPH" line so I took it off again and added a TINY bit more solder to the counterweight. After testing the needle again, it now sat right on the "0 MPH" mark. Depending on how out of balance the needle is, you might need to do this several times. The reason you want to add a very tiny bit of solder at a time is that solder contains lead which is very heavy and it is easy to add more if you need it but once you have more solder melted onto the counter-weight than you want, it is very difficult to remove, if not impossible. Sort of like adding salt to your food. Once it's on there, there's nothing you can do about it if you add too much. So, take it one very small step at a time, and test the needle carefully each time and it should do the trick for you.