I have an intermittent problem on my 1995 Honda Odyssey.
Most of the time, it runs just fine. When I bring it out on the highway for more than an hour or so, the speedometer fails. Within a minute of the speedometer failure, the solid green light that tells me what gear I am in goes to flashing green. Within a few minutes of that, the “check engine” indicator lights up.
The car has no problem shifting gears.
If I turn the engine off and then turn it on again, everything is just fine. It will stay fine until I take the car out on the highway again. (For me, that could be weeks!)
I suspect an intermittent problem in the speedometer or the VSS. But how can I tell which to replace if the failure is this intermittent.
I vote for the VSS. I don’t think a speedometer malfunction would do anything related to the transmission.
Since the check-engine light went on, get the codes read. That will probably help narrow it down.
Engine trouble codes are flashed by the check engine light (symbol). Transmission trouble codes are flashed by the D4 light. Both lights are caused to flash their codes by putting a small paper clip in the blue, two wire connector below the glove box, or behind the right side kick panel.
If you could jumper the connector when the trouble lights flash, you could get a better idea of what is happening with your engine and transmission.