1999 Accord EX V6 suddenly stalls while driving

honda
accord

#1

While driving, the tach and engine will randomly rev slightly and then drop to 0, stalling the car. Sometimes it just shuts off without rpms increasing. This happens with manual acceleration and cruise control.

Power steering goes out, the engine dies, but no check engine light appears. If I attempt to start the car immediately, it revs without turning over. If I wait 8-10min, it will start again; jumping it also works.

Things I have replaced attempting to address this issue:
· Battery
· Spark plugs
· Ignition control module
· Ignition coil


#2

This is just a WAG based on my experience as an Accord owner of the same vintage. It could be a fuel pump issue.


#3

It revs without turning over is another way of saying it turns over but does not start.

When it does not start, the first test is to see if the engine is lacking fuel or is lacking spark. It’s almost certainly one and not the other. A test for no fuel is to spray starting fluid into the throttle body while turning the engine over and see if it’s firing up and acting like it’s almost starting. A test for spark is to have a spare spark plug that you clamp or tie onto engine metal, so it’s grounded. Plug an ignition wire onto it and observe while turning over the engine. Fat sharp intense regular spark, or weak or no spark?


#4

The problem might be caused by a faulty PGM-FI ECU main relay.

This relay supplies power to the computer/fuel injection system.

These relays are a well known problem with Honda vehicles not starting/stalling when the solder joints crack in the relay.

Tester


#5

+1 to Tester’s suggestion. If when you turn the key to Run (not all the way to Start) the fuel pump does not run, that’s a strong clue. If you’re in a quiet place, you should be able to hear the fuel pump run for a couple seconds each time you turn the key from Off to Run.


#6

+1 to @tester
A friend of mine just recently had similar symptoms on his daughter’ Civic of the same vintage, and it was traced exactly to that relay.


#7

@Tester, I replaced this part two days ago and so far it’s working well! Thank you so much for the help.


#8

If the problem surfaces again you need to consider an ignition switch problem. Some Hondas of this era are under a Recall for failing switches.

The engine control system along with the high current draw fuel pump is what does the main relay and the ignition switch in by burning the internal contacts.
Think of it as one weak link in the chain after another.