Recently my wife's Accord will just stop while you are driving. Just like you turned the key. If it is left in gear and you are moving, often it will just bump start itself and away you go. Other times you have to use the key to restart. It actually happened to me yesterday but the wife says she has seen it before (why I'm just hearing about it now is another issue). I have previously (2003) had the ignition switch replace due to a recall. Honda now thinks it may be the main relay. Before I spend the $100 on a relay and relace it myself on spec does anyone have any ideas on how I can diagnosis this. Codes won't help and the car "thinks" it has just been normally shut off.

Mike
1999 Accord DX

 

Your problem doesn't have the symptoms associated w/ Main Fuel Relay failure, at least that I've seen. Typically, the MFR will quit when attempting to start after car has been sitting in warm sunlight. Engine will turn over w/o a hint of starting. MFR disables the fuel pump which you can hear for 2-3 secs when you turn the keyswitch to ON but not to Start. Unless the car will not start, it will be difficult to diagnose the problem.

Engine stalling can occur due to inadequate air flow, dirty/blocked IACV and dirty throttle plate. Usually a very low idle speed will be present also.

EGR can stick open after a coast to a stop. W/ EGR stuck open the engine overleans and dies. However, i think this should set a code since EGR valve position would be incorrect for engine condition.

I would suggest starting w/ cleaning IACV and throttle plate. Also be sure your plugs, wires, and distributor cap are in good condition.

good luck

 

Thanks Texasonda. Now of course I need to find out how to clean the IACV (Idle Air Control Valve?) and the throttle plate. I am NOT a mechanic, although I have a surprising ability to replace anything once I know where it is... Am I likely to find tips in the DYI section? I must say though that the car runs fabulously at all speeds. I have seen this once at about 30 kmh but wife now reports it at various speeds. Idle is good, no lights or odd behaviors, everything else seems just fine (although the ABS light did come temporarily the other day but I attribute that to the dusty salty roads). I'm thinking dirty throttle plate/Idle Air Control Valve would present amore repeatable symptom).

 

IACV is Idle Air Control Valve, sometimes EACV for Electronic Air Control Valve in Honda-speak. I would still suggest doing this maintenance. You should be able to find w/ a search. A shop manual is also a nice addition for DIY.

good luck

 

I agree, anything that has not been donethat should be done, should be done...

This problem is not a stumble or bad idlethen stall. None of hte symptoms I would expect w/ a fuel problem. This is driving donw the road and it appears that someone has turned the key. The car turns OFF.In my one experience I pushed in the clutch and restarted w/ the key. My wife reports not doing anything (leaving the key in the run position) and thecar effectively bump starts itself. It has all the symptoms of an electical problem. Much like the symptoms described by the recall for the ignition module (or it was it theswitch).

 

Hey Mike,

I just had this happened to me yesterday. This is the 2nd time in the past 6 months. I have a 99 Accord Coupe V6. Are you able to find a solution to your problem?

Thanks
Gene

 

ultragc: did you have the recall done to your vehicle? (if it affects your particular model that is) if not then I'd start there...

 

Did you happen to notice if the Check Engine Light and Alt light came on when the car quit? If no lights came on then power was not available to ECU, which means most likely the keyswitch is the problem. If the CEL and Alt light came on immediately, this would suggest loss of fuel pressure. Loss of fuel pressure (main fuel relay orfuel pump) seems unlikely since it restarted so easily. Keyswitch is about the only mechanical part that could fail and cause interruption of the power to the ignition.

An intermittent coil or ignitor is a possibilty, however this failure should set a code since the ignition output signal would be interrupted.

It's a little tedious but you can rig a "tell-tale" light to the blk-yel ignition power supply light with the light in the car where you can observe the light when a shutdown occurs. I use the snap-on wire splices to minimize damage to the wiring when splicing the wiring.

good luck

 

The problem is the ignition switch that has been under recall (http://www.visualimpressions.ca/switch/)

If you get under the dash and do a little wiggle wiggle the car stops. Get the new part tomorrow, the Honda dealer has basically told me to go pound sound as this was previously done in 2004.

 

Yes I did. Anyway, here's the update:

I took it to the local mechanic. They think its the gas filter that's dirty and clogging thinks up. So they performed cleanup on the fuel injection system by injecting some solutions into it. It created a huge amount of smoke and it will last for a week... according to them. This is supposed to burn out the junks in the system. Anyway, we'll see.

In addition, I did a OBD code check on my car, it came back with P0420 and P0401. Looks like I have more work ahead of me. Damm it...