Transmission/ Electrical Issue
 

1999 Honda Accord- 4 cylinder- automatic
180,000 miles
Over the past year, the car has at random times done the following:
while driving, the tachometer and speedometer both move with the maintenance required light coming on and the transmission not engaging. This lasts about 2 seconds, then everything is back to normal. I have not been able to pinpoint its occurance to a particular gear shift, although it usually happens when I am in a lower gear. It does not occur every day, sometimes it does not do this for a week or 2 and sometimes 2 times in one trip.
On Saturday, this occured again as I was slowing down to turn, but the transmission never re-engaged and the car shut down. It would not crank for the next couple of minutes, then it cranked and I was able to drive with no problems.
Anyone have ideas? What is casuing this, how can I fix it?

Is the check engine light on? or does it come on when the problem arises?

Is it the original transmission? The 98-02 automatic transmissions are notorious for dying. However that does not explain the maintenance reqquired light coming on and the tach and speedo messing up.
Could be something electrical.
A bad vehicle speed sensor will cause shifting problems and make the speedometer mess up, but it will also cause the check engine light to come on. I have never heard of a bad VSS doing anything to the tach though.

The maintenance required light comes on when the problem is occuring and goes off after. The check engine light is constantly on due to an emissions issue (the 2 codes it gives are both emissions related).

What 2 codes (the actual numbers)?

The maintenance required lamp is a funny clue. It's supposed to come on based on mileage alone, not a functional test of any kind. Having that lamp come on & go off might indicate problems in the wiring harness.

Check Engine Codes
 

P1491 according to my service bulletin EGR valve insufficient lift
P0401 EGR insufficient flow

After talking to some people, it sounds like I may have 2 seperate problems (unrelated). The transmission problem may be electrical- bad connection. The car actually turning off is a seperate problem- possibly a fuel pump issue??
Yesterday the car turned off right after it started, then started with no problems. The car was driven a little further and turned cut-off, then would not start for a couple of minutes, then started and had no problems the rest of the drive.
Any ideas? Some have said that there car has done wierd stuff when the fuel pump was on it's last leg- does the car turning off sound like a fuel pump issue? or something else?

If it were a fuel pump issue the oil & alternator warning lights would come on.

If it were a flaky ignition switch, those lights would not come on because the ECU thinks you've switched off the car.

A bad main relay normally prevents starting, but it's unusual for that to cause stalling when the car is already running. But the main relay is known to be a common problem, and it would cause the fuel pump to stop running.

I don't understand any connection with the maint.req. light. Unless the maint.req. counter is at that in-between stage where it flashes on startup but doesn't stay ON. That would flash & go out each time the ignition switch goes off & on.

Welcome newbie TiltRotor!
Good idea. Low system voltage can do all kinds of crazy things.

My battery volts seem fine (12-14 volts), but I will run by Autozone and have it checked out.