I have a 1994 3000gt that just recently put a rebuilt engine in. Sometimes the odometer works, and then sometimes it doesnt, while the needle just goes from 0 to 10mph up and down forever.

Is it a loose wire?

ThankYou

 

Loose wire on the speed sensor, or the sensor went bad. It is on the passenger side of the engine bay near the clutch hydralic line.

 

Wow, I thought I was insane. This is happening to me too, and I have no clue why. I've checked the Vehicle speed sensor, checked all the harnesses,swapped ECUsto make sure it was broken. During the rebuild, I did drop my steering column for an ABS delete (had to pop the column out of the rack to route new brake lines). I thought maybe when I dropped the steering column, wires maybe got squished or unplugged. I also double checked my boomslang harness connections to make sure they are tight, but I haven't checked it for continuity yet. (I don't know if the Vehicle speed output goes to the ECU and then goes to the gauge or not....)

It's really strange and intermittent though. Sometimes it works normally, sometimes it doesn't work at all. Sometimes it get's stuck at 20MPH and doesn't move for a long time before going "dead" again.

My EGT gauge was doing a similar thing, but all of the rest of my electronics worked like normal. After my 500 mile break-in, my speedo and EGT mysteriously have been working consistently.

So I don't have any advice, but I'll be watching this thread to see if there are any suggestions.

 

Easy fix guys!


what you have to do is remove the speed sensor from the transmission and inspect the little gear that is attached tothe sensorby a clip. Some times the clip becomes loose and comes off the speed sensor leaving the gear and its spindle to move freely only to have the oil pressure hold it upright (this explains the reason why it works and sometimes doesnt, as the oil pressure varies). Remove the speed sensor, and inspect it, mostlikely it is the clip. If not then replace the whole sensor.

Thank you.