Ok, I'm assuming the issue is with my speedo and that I'll have to replace the whole unit.
The speedo reads about 30% too high (it says 130 when I'm only doing 100) but my odometer is bang on the money.
What part needs replacing?
84 Jetta
The needle is off on its orientation? It is consistently that much higher than every speed?
The only accurate speed reading I get is 0. 50 reads about 65 and 100 reads about 130. I'm not 100% sure that it's quite that linear, I'd have to check it with my GPS again. Weird eh?
Mine was off 15 too high after i modded my cluster, "i took off the needle" so i opened it up again and drove around for a bit with my gps and kept pushing the needle down until it read right. I had to brake off the plastic stop pin "early 90's mk3 cluster" and it points almost right down now but it reads 100% accurate
Mine does that too, and the needle shakes in the low range. If I'm going 50, it reads 60, then stretches to about 15 off by 401 speeds...
If the needle shakes that's usually an issue with the speedo cable binding slightly.
I've heard in mk1s anyways at least ,
sometimes a bad ground wire can allow grounding to try and occur thru the speedo head with disasterous results. It'll heat the springs and other delicate items in the speedo head.