[kdeiber]

I have a 97 outback (some parts are 96, I replaced the coils and they were 96 not 97 but the vin says 97) that began sputtering and stopping a little over a year ago. When it runs it runs fine, but after driving somewhere and letting the car sit for 10+ min I would come out and it wouldn't start. Wait a few hours and it would start back up and drive home. This happened in some pretty inconvenient places like Teton National Park in the middle of the night. I replaced the fuel pump a few months before this started to give me problems, and the fuel pump relay as I read threads of this being the problem. The relay is working fine, I can feel it click when the ignition is turned even when it won't start. I don't think it's the fuel pump as it works fine much of the time. I don't know if it's electrical or fuel related. I can try to see if I'm getting spark but I can only test the problem when it won't start. There will be stretches of weeks where it starts (sometimes after 1 or 2 attempts) fine and occasionally it just won't start and I'll have to wait several hours, up to a day. Once it was stuck in a parking lot and wouldn't start after trying on a few different days. I decided to tow it home, rolled 50 yards down the parking lot (it was a big angled dirt lot in the mountains) and after rolling it started fine and drove home. The last time it wouldn't start I tried to roll it but it would not let me take the transmission out of park. I waited a few hours and it started back up and drove home.
Any ideas on what this might be? If it's fuel how can I diagnose? If it's electrical?
Thanks for the feedback,
Kevin

 

[ron917]

Failing cam or crank position sensors can cause problems when trying to start a hot engine. The signal from that type of sensor gets weaker when it is hot, so one that is on the way out may not produce a strong enough signal when the car is trying to start hot.

Loose or dirty electrical connections can cause all manor of intermittent troubles. It's hard to be specific with this, but check every connector you can find. I've had connector troubles that took weeks to find but only seconds to fix at no cost.

 

[Don Weldon]

My 97 outback is having similar intermittent start problems. Have you found the source or fix for your problem?

 

[idosubaru]

if you have a check engine light - get the code.

if not, it is a good idea to swap in another cam or crank sensor. they do fail and cause this exact issue - no start after being warmed up. and they are super easy to replace - one bolt each.

i'd go with used units though as they are pricey new. they don't fail very often so it's not like they're worth very much with almost zero demand.

 

[1 Lucky Texan]

if it doesn't crank, could be a neutral safety - maybe try putting the car in neutral instead of park? Also, try tapping on the starter in case the solenoid contacts are worn.

if it cranks but won't start, next time you feel it may fail to start, try the 'clear flood' procedure, floor the gas pedal and hold it down while cranking.

but yeah, also seems like CAS is failing when warm.

 

[idosubaru]

Also, try tapping on the starter in case the solenoid contacts are worn.

that is a good call. very simple to do and you feel really cool when it works!

 

[RebelElf]

Solution to '97 Outback intermittent/no start

Just a week ago I got the P1507 code so I pulled apart and cleaned the Idle Air Control Valve (IACV) and replaced the MT Neutral Safety Switch (NSS) - see that post under "Engine Light P1507". It ran SO nicely afterwards that I figured my wife should enjoy driving it too. So she drives it a few days and then says it's having trouble starting - it would crank but not fire, or crank for 10+ seconds before starting. Yet it ran beautifully when it did run. (What is it with wives and cars?! Their breakdowns always seem to happen when together, and right after I just fixed her - the car, not the wife.) Here's the symptoms and rundown:

1) After I got her running last week from the P1507 IACV and NSS fix, she ran glassy smooth and very peppy and would literally start and restart any time, anywhere, with barely a flick of the ignition. And never threw any CELs.

2) Then, few days later, she began to crank longer - maybe 3-5 seconds. And after shutdowns, she would start again after about 2-3 second crank. If the car sat longer, the cranking took longer, 10-15 seconds - as if the fuel line bled off or something. After setting overnight once, she started fine the next morning and I could hear the pump whirring when the ignition was turned to "on". But usually after setting overnight would not start the next day.

3) Ultimately, within days the cranking was lasting forever, and she quit starting. I tried intermittently a dozen or two dozen times to start the car. And at this point I could not hear the pump whir when turned to "on". (Please note that I have mentioned "crank" here several times meaning that this never had anything to do with a poor battery or a bad starter.)

4) So I took the fuel pump out (again!) and bench tested it - 12 volts from the charger and she purred like a kitten as usual! So I believed the pump wasn't bad. I reinstalled the pump, turned the key to "on" and could hear it whir again. And the car started again! I also hooked up a hose and glass jar to the fuel line off the fuel filter and she pumped fuel five times during ignition "on" and a full fuel stream when going to full "start". I tested the pressure at ignition "on" and it popped up to 10 PSI. At full start the pressure just blew my gauge hose off spraying fuel all over. Extrapolating a really fast needle spike on the gauge, I would say pressure was well into the 40's.

5) I hooked up the fuel lines again, and she started right up. I then cycled the key off and "on" about 5 times, each time hearing the pump whir - thinking there's nothing wrong now. Until the sixth time when there was silence. And she would not start again.
*** Now certain forums have mentioned a "flat spot" in the pump where the pump is in purgatory like the fields are balanced perfectly neutral or something and the commutator can't spin up. But I didn't believe this was the cause. I believed it was the relay because the pump spun just fine on the bench. I could hear relays clicking in the dash, but I had no proof that wasn't a malfunctioning fuel pump relay. So I had previously purchased a new fuel pump and pump relay expecting to install one or the other - I went for the relay first - it's cheapest. ***

6) Man is that relay ever a Subaru engineering mis-creation - they should have to drive and fix what they build! It was like finding BHO's brain during a colonoscopy - which may be easier. I didn't have to remove the whole dashboard, but I had to cut loose the security alarm box, cut some useless sharp plastic doohickey out of the way, pull several connectors and bend wire harnesses out of the way, to force my hand way up and pinch the green connector tang lose. It hurt. I inserted the new relay into the connector and holding it in my hand checked for the ignition "on" click - it clicked. Since it is impossible to remove the old relay off the fender without yanking out the entire dash, the new one will dangle underneath just fine the rest of its life. But I didn't hear the fuel pump whir.

7) So I pulled the fuel pump (a 3rd time!) and bench tested it. Suddenly, 12 Volts had no effect on the motor. No matter how I twisted and contorted the contacts 30 different ways the motor DID NOT SPIN up. So I installed the new fuel pump and reinstalled all back in the car. I turned the ignition "on" and the pump whirred. *** I went back to the bench, tried the old fuel pump again 10 ways with 12 volts and nothing. I slammed the old motor on the concrete floor and tried 12 volts again - this time it spun up. Almost 100 times thereafter I could not get the motor to repeat its "flat spot" or stall on the bench. ***

8) I put the lower dash, connections, alarm box, and fuel pump cover and seats all back together and tried ignition "on". There was click, and there was whir. And there was fire. The car started instantly - 5 times in a row, and performed just like stock on a test drive.

I am rather satisfied; not as peppy as before, but the fuel pump may just need to break in. I believe the fuel pump was the true solution - the relay was just incidental to diagnosis. And the car still never threw any CEL's. If this was the car's first fuel pump, then the pump went 210K miles - but I am also not the car's first owner.

Good luck with you and yours. God Bless.

 

[RebelElf]

*** UPDATE 4.0 ***

Almost 3 months since the new fuel pump and the car is running great under all conditions and has exhibited zero problems. Anyone with a P1507 or P0301-4 cylinder misfire should really look first at their fuel pump. In retrospect, all of my misfires, stalling, non-starts, and intermittent running "problems" coincidentally compounded in a very short amount of time, and were all similar to fuel delivery shortages; and lead up to replacing the fuel pump anyway. Everything else I replaced or cleaned was inconclusive, incidental, or an immaterial solution to obtaining real improvements in the cars behavior. Use your intuition and guts folks. They're just cars. Good Jap cars. It's not brain surgery.
And thanks goes to people who post on these forums.