If so...there is a small hole at the leading edge of the lower unit, that supplies the necessary pressure to move the gauge needle. Look for an obstruction on, or in, this hole.
Most people use a drill bit slightly smaller than the opening. Turn it by hand very slowly...you don't want to force anything further in, and you do not want to make the hole any larger!
There are other things to look for...but this is usually the first thing that works.
Re: 218LS speedo not working...help troubleshooting
Does a fantastic job. I am very pleased with it for towing. It's no turbo diesel, but for what it is, does great. I couldn't talk my GF in to something bigger, so it's a great compromise.
