Just bought a used 03 rex, with 28k on it. Love the car, but one week after installing a boost gauge in the cluster, the speedo has stopped working. I shouldn't say stopped, cause when I hit the brakes hard it seems to work, and every now and then it will bounce near the speed I think I should be going (according to rpm and gear choice). Mostly it just sits a zero. Both the odometer and the tripodometer work.
Anyone have any ideas? I have checked the fuses, and looked under the dash for loose connections, but to no avail. I don't think the boost gauge did it cause that was over a week ago, and I haven't even tapped power for its lighting yet. Any help would be appreciated.
Sorry for the long read.