04 Forester won't fire on SECOND start

[Tricia Nadeau]

Recurring problem with my '04 Forester: In cold weather (<15F), the
car will start fine from a cold start. After a very short drive (~2-3
minutes), I shut the car off and leave it for 1-2 hours. Trying to
start it after letting it sit that hour or two will result in it
cranking endlessly but never catching and firing. Another 6-8 hours
left sitting there, and it starts fine. The problem is intermittent,
with no clear common threads other than cold temps and short drive,
although sometimes those conditions mean nothing and it starts fine.

No one seems to be able to figure this out - not generic garages, not
the Subaru dealer. Not the spark plugs - they were replaced after the
first incident, and the problem persisted anyway. Not a flooded
engine - mechanic found no evidence of flooding and the Subaru car
manual fix of flooring the gas upon starting does nothing to help it
start. Not the battery - cranking is strong, and even draining the
battery with excessive cranking, it still starts fine after 8 hours,
even though at that point the battery is weaker.

Any ideas? Similar experiences? It's very frustrating to always fear
getting stranded somewhere because the stupid thing won't catch.

 

[Dave__67]

Recurring problem with my '04 Forester: In cold weather (<15F), the
car will start fine from a cold start.  After a very short drive (~2-3
minutes), I shut the car off and leave it for 1-2 hours.  Trying to
start it after letting it sit that hour or two will result in it
cranking endlessly but never catching and firing.  Another 6-8 hours
left sitting there, and it starts fine.  The problem is intermittent,
with no clear common threads other than cold temps and short drive,
although sometimes those conditions mean nothing and it starts fine.

No one seems to be able to figure this out - not generic garages, not
the Subaru dealer.  Not the spark plugs - they were replaced after the
first incident, and the problem persisted anyway.  Not a flooded
engine - mechanic found no evidence of flooding and the Subaru car
manual fix of flooring the gas upon starting does nothing to help it
start.  Not the battery - cranking is strong, and even draining the
battery with excessive cranking, it still starts fine after 8 hours,
even though at that point the battery is weaker.

Any ideas?  Similar experiences?  It's very frustrating to always fear
getting stranded somewhere because the stupid thing won't catch.

I've heard the crank angle sensor can get like this when it's starting
to fail.

Any trouble codes stored?

Dave

 

[1 Lucky Texan]

Recurring problem with my '04 Forester: In cold weather (<15F), the
car will start fine from a cold start.  After a very short drive (~2-3
minutes), I shut the car off and leave it for 1-2 hours.  Trying to
start it after letting it sit that hour or two will result in it
cranking endlessly but never catching and firing.  Another 6-8 hours
left sitting there, and it starts fine.  The problem is intermittent,
with no clear common threads other than cold temps and short drive,
although sometimes those conditions mean nothing and it starts fine.

No one seems to be able to figure this out - not generic garages, not
the Subaru dealer.  Not the spark plugs - they were replaced after the
first incident, and the problem persisted anyway.  Not a flooded
engine - mechanic found no evidence of flooding and the Subaru car
manual fix of flooring the gas upon starting does nothing to help it
start.  Not the battery - cranking is strong, and even draining the
battery with excessive cranking, it still starts fine after 8 hours,
even though at that point the battery is weaker.

Any ideas?  Similar experiences?  It's very frustrating to always fear
getting stranded somewhere because the stupid thing won't catch.

Dave67 has a great reply. Intermittent crank or cam angle sensor.

I'm wondering if you feel moisture is a factor. Either rain/snow or
possibly condensation in the engine compartment. Cracked sparkplug
wires or coil pack/coils could prevent the car from starting.

 

[bugalugs]

Dave67 has a great reply. Intermittent crank or cam angle sensor.

I'm wondering if you feel moisture is a factor. Either rain/snow or
possibly condensation in the engine compartment. Cracked sparkplug
wires or coil pack/coils could prevent the car from starting.

How about the air temperature sensor. Could it be sensing a warm start,
after your short run and not enriching the mixture for what is really a
cold start. Just a thought.

 

[weelliott]

Recurring problem with my '04 Forester: In cold weather (<15F), the
car will start fine from a cold start.  After a very short drive (~2-3
minutes), I shut the car off and leave it for 1-2 hours.  Trying to
start it after letting it sit that hour or two will result in it
cranking endlessly but never catching and firing.  Another 6-8 hours
left sitting there, and it starts fine.  The problem is intermittent,
with no clear common threads other than cold temps and short drive,
although sometimes those conditions mean nothing and it starts fine.

No one seems to be able to figure this out - not generic garages, not
the Subaru dealer.  Not the spark plugs - they were replaced after the
first incident, and the problem persisted anyway.  Not a flooded
engine - mechanic found no evidence of flooding and the Subaru car
manual fix of flooring the gas upon starting does nothing to help it
start.  Not the battery - cranking is strong, and even draining the
battery with excessive cranking, it still starts fine after 8 hours,
even though at that point the battery is weaker.

Any ideas?  Similar experiences?  It's very frustrating to always fear
getting stranded somewhere because the stupid thing won't catch.

I had a very similar experience with a 96 saturn SL2. The temperature
sensor turned out to be the issue. It was my wife's car and it woudl
start fine the first time, but if she were runnign errands and tried
to start it minutes after she shut it off, it would crank for minutes
before finally coaxing it to start. She never had an experience where
she tried to start it 1 to 2 hours after shutting it off, only minutes
or over night. Over night always worked beautifully.

I have a few theories as to the mechanism behind this, but I don't
know how valid they are. I do know for a fact though, that with that
car that was the problem. So I'd suggest replacing the temperature
sensor and see if that does anything. For the saturn it was a 27
dollar part.

Good luck,
Bill

 

[S]

Hi Tricia, Bill, All!

I had a very similar experience with a 96 saturn SL2. The temperature
sensor turned out to be the issue. It was my wife's car and it woudl
start fine the first time, but if she were runnign errands and tried
to start it minutes after she shut it off, it would crank for minutes
before finally coaxing it to start. She never had an experience where
she tried to start it 1 to 2 hours after shutting it off, only minutes
or over night. Over night always worked beautifully.

I have a few theories as to the mechanism behind this, but I don't
know how valid they are. I do know for a fact though, that with that
car that was the problem. So I'd suggest replacing the temperature
sensor and see if that does anything. For the saturn it was a 27
dollar part.

The software for my OBDII reader has a channel for monitoring the
intake air temperature, and coolant temperature (as well as a ton of
other stuff). I don't know for sure that the Subaru ECU will output
this data, but if it does, that would be an easy way to check the
above.

I have the Elmscan tool and software (runs on my laptop), but
doubtless any OBDII reader will have similar functionality.

This is probably what you will need to diagnose the problem in any
event; throwing new parts at the problem can get expensive, and divine
intervention is problematical for most of us ;-)

I need to see what the CEL in my wife's '02 Forry is complaining
about, anyway (knock sensor, I'll bet: been there); I'll look to see
if the temperature outputs are available while I'm at it, and let you
know.

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

 

[Tricia Nadeau]

Hi all, thanks for the input.

Fair warning, I am pretty car-dumb, but to answer questions...

-No, I don't believe there have ever been any trouble codes that
showed up with this issue
-Other people have suggested it being a moisture issue, and maybe it
still is, but I tend to think no. The things makes it through wind,
rain, snow, inside and out, and generally no problems. All of this
only happens when it's very cold, so even if it was moisture and
perhaps something to do with freeze/thaw somewhere, why would it be
fine below freezing (in 20s/high teens) but not when further below
freezing? I guess I just don't know what to say there. I never
noticed anything to do with moisture as being common to all of the
times that problem showed up

Next time it happens, if they still can't figure it out, I may suggest
to my mechanic the crank/cam angle sensor and the temperature
sensors.

Someone else suggested to me that it could be an intermittently flaky
fuel pump relay (owing to cold and it perhaps not making a good
physical connection because of size changes in the cold?) Anyone here
know anything about that sort of thing?

Thanks again.

 

[1 Lucky Texan]

Hi all, thanks for the input.

Fair warning, I am pretty car-dumb, but to answer questions...

-No, I don't believe there have ever been any trouble codes that
showed up with this issue
-Other people have suggested it being a moisture issue, and maybe it
still is, but I tend to think no.  The things makes it through wind,
rain, snow, inside and out, and generally no problems.  All of this
only happens when it's very cold, so even if it was moisture and
perhaps something to do with freeze/thaw somewhere, why would it be
fine below freezing (in 20s/high teens) but not when further below
freezing?  I guess I just don't know what to say there.  I never
noticed anything to do with moisture as being common to all of the
times that problem showed up

Next time it happens, if they still can't figure it out, I may suggest
to my mechanic the crank/cam angle sensor and the temperature
sensors.

Someone else suggested to me that it could be an intermittently flaky
fuel pump relay (owing to cold and it perhaps not making a good
physical connection because of size changes in the cold?)  Anyone here
know anything about that sort of thing?

Thanks again.

I seem to vaguely recall some Outbacks or other models that had a
problem- say- backing out of the garage, then not restarting. That is
a VERY short trip. Maybe someone will remember that or try asking at
www.ultimatesubaru.org or www.nasioc.com .