Hey guys, My speedometer currently only shows 90km/hr whilst driving. It'll drop back to 0km/hr when stopped but jumps back when the car starts moving again. I think it's to do with the earth of the transmission speed sensor (its grounded to a bolt on one of the gearbox supports), mainly as my exhaust used to have a lot of holes in it which caused a bit of a carbon build up underneath the car. I got a full custom headers-back exhaust in May and the speedo stopped working about 2 weeks after. The speedo has gone back to normal a couple times (once after driving through bumpy roadworks and once after it was put on the dyno, but each time only lasted a few hours). I have tried cleaning the earth by spraying degreaser on it and scrubbing around it which used to make it work for a day or so but has slowly stopped affecting it. I cant get the bolt off as the exhaust blocks any tools that would fit and I'm not confident enough to pull the exhaust off. The odometer isn't affected, neither is the tacko or anything else on the dash cluster. Just wondering if anyone has experienced something similar or if i'm on the right track in believing its the earth causing the issue? It's been about 6 months no speedo so it's about time i stop procrastinating XD video for example: thank you!
yup had exactly the same thing happen to my old 300kmph speedo I installed like 15 years ago. Worked great for a few months and then the needle would go to 100kmph and stay there no matter what speed i was going. Took the speedo to a speedo repair shop and they said the speedo was burnt out and needed replacing completely, so id say you need a new speedo im afraid
I had a speedo that wandered from the correct speed to any speed. I pulled the speedo out of the cluster and on the second attempt I found the solder joints that holds the speedo motor to the board were cracked. Over time the weight of the little motor cracked the joints. Bob
