Engine Turns Off Randomly

Hi,

Some far-fetched ideas to try after you exhaust the "usual suspect" list:

Your ignition switch may be dirty or worn. My "door dinger" works intermittently, and the headlights would go "off" when switching from low to hi-beam when I got my '90 Loyale. It lived its "first life" in a very dusty environment, and both problems responded well to repeated applications of aerosol contact cleaner to the respective switches (available at the auto parts store.) My "4wd" light on the dash (switchable system--switch on shift knob) is also intermittent--same apparent cause, but it responds better to a shot of WD-40 than the contact cleaner.

My g/f carries around a huge assortment of trinkets on her key ring--I don't know how much they weigh, but mechanics have told me this can put extra strain on the ignition switch and cause wear (which could then cause an intermittent open circuit over bumps and such.)

Good luck finding the problem! Intermittent stuff's always the worst...

Rick

While I haven't seen this on a Legacy, I have had similar problems with other makes and models. Usually has turned out to be ignition components failing. I'd try swapping in another ignitor module for starters. I think it is located on the fire wall behind the engine on these cars; perhaps someone on the group knows for sure? As Rick suggests, your key switch could cause this symptom as well, especially a "well used" one. Not too hard to replace the switch; IIRC just a couple screws holding it to the back side of the lock cylinder/steering lock mechanism. Unplug the connector, and it's out. Other things to look at might include the injector resistor pack (loose wiring), the fuel pump (again, loose wiring), or even the large connectors for the engine wiring harness (plugged in all of the way? Water or other contamination present?). ECU seems unlikely, but possible I suppose, and it _could_ be something as simple as a loose fuse in the fuse box, so inspect that as well. Alas, the easiest way to diagnose problems of this sort is to swap in "known good" parts until the problem goes away; prohibitively expensive if you're buying new bits from the dealer. I'd suggest finding another Legacy of similar vintage to borrow from. Perhaps someone you know has one and would be willing to help out? Hope this at least gets you started.

ByeBye! S.

Steve Jernigan KG0MB Laboratory Manager Microelectronics Research University of Colorado (719) 262-3101

If you promise not to laugh....

I had a Pacer that had that problem. Okay, it was 30+ years ago, but it turned out to be a bad wiring harness.

BTW, the Pacer was a great car, small on the outside, big on the inside, handled and rode like a dream- so stop laughing.

I had that problem with my Alfa, due to bad wiring between the battery and the ECU. I'd definitely look at the power circuits.

One thing to check - do the lights go off when the engine stops?

Does the radio stop playing when the engine stalls? Have you checked for any stored trouble codes? I would think if you lose the radio than the ignition switch looks pretty good as a possible source of the problem.

In my case it was a dodgey connection to a relay base. Ignition turned on the relay which fired up the ECU and fuel pump. Hence my point that you should check all the main power wiring from the battery to the ECU as well as the ignition circuit that activates it.