Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

Photo
- - - - -

Hard Cold Start Issue


  • Please log in to reply
17 replies to this topic

#1 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 15 December 2008 - 08:37 PM

Hi All,
Been lurking for awhile now and thought i'd finally do some posting. I have a small problem that just won't seem to go away....

What I have:
99 Legacy Outback 2.5l jdm swapped motor
950 CCA Battery (Napa Emergency Vehicle Battery)
Premium fuel

Problem:
Hard starting on cold mornings. If it's 40 degF it'll start after about 10 sec of cranking and finally catch then idle just fine and it's never an issue again. It's just the initial start. At 5 degF it cranked for about 25 sec and wasn't sure if it'd catch but it eventually did and then ran fine. Started fine for the rest of the day but it was relatively warm. The car runs fine once it's started.

What I know and have thought:
1) Eng Temp Sensor: replaced and didn't change anything
2) Fuel bleeding back into tank somehow.
a) fuel pressure is 40-42 psi with ig on
B) Engine running: fuel pressure is 37 psi w/ press reg vac line disconnected (4 less than range in FSM)
c) Engine running: fuel pressure is 32 w/ press reg vac line connected (+2 of FSM)
d) fuel pressure drops to 20psi after sitting for about 15 min, and further if sits longer

Codes:
P0130, P0500, P1101, P1121, P1540

Questions:
1) would those out of spec pressures contribute to this problem. I'd hate to sink $200 into a new fuel pump/pressure regulator to find it doesn't do anything.
2) should the pressure be maintained after the car is shut off indicating a faulty check valve or is this normal. if so, could installing an inline check up by the tank solve the problem?

Any ideas what might be creating this problem would be really helpful. I hate to take it to the dealer because they'll say it runs just fine and won't actually wait for it to get cold enough to be a problem.

Thanks in advance,
Mike

#2 frag

frag

    Soob shade tree mechanic

  • Members
  • 1,777 posts
  • Montréal, Québec, Can.

Posted 15 December 2008 - 09:39 PM

Hi,
The only thing I can contribute is that the fuel pressure seems normal and the fact that it's begining to go down after 15 min. is also normal.
I have a fuel pressure gauge on my car and the same thing has been happening since the beginning without ill effects.
P0130 has to do with the front O2 sensor and P0500 with the speed sensor. I don't see how a problem with these could produce the symptoms you're having. I dont know about the other codes.
Good luck and wait for further help.

#3 98obster

98obster

    USMB is life!

  • Members
  • 248 posts
  • Greeley

Posted 15 December 2008 - 11:20 PM

a question, where is the fuel pressure measured-before or after the fuel filter?

kinda sounds like a vacuum leak or too lean (good ole not enough choke on a cold engine like).

how about cranking it for a couple seconds and stopping and then trying it again, instead of trying to start it from one long try?

#4 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 16 December 2008 - 12:24 AM

Hi All,


Codes:
P0130, P0500, P1101, P1121, P1540

Thanks in advance,
Mike


130 - front 02 snesor circuit malfunction
500 - vehical speed sensor malfunction
1101 - neutral saftey switch high m/t
1121 - neutral position switch high m/t
1540 - vehical speed sensor 2 malfunction

did you hit or runover something?

Cold start issue - what is the fuel pressure when the car is first cranked and stone cold? You have multiple issues here. Get a used fuel pressure regulator, but i want to know what the gauge reads after a cold overnight soak.

nipper

#5 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 16 December 2008 - 07:52 PM

thanks for all the quick replies.
i'm at work until tomorrow morning at which point i'll check the pressure after tonights last drive (about a 12 hr sit w/o running).

I have the pressure gauge post filter at this point but could easily move it pre filter. There are no signs of filter restriction in the way it drives making me think the filter wouldn't reduce the pressure but who knows how finicky these soobs are....

I'm also going to try the ECU reset tomorrow via pulling the battery leads off and letting it sit for an hour or so. We'll see what that does. I did clear the codes via my scanner but they came back once i started the car again....

thanks again,
mike

#6 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 17 December 2008 - 01:25 PM

so i'm home now and with regards to the fuel pressure it bled to 0 in approximately 2 hours after shutting it off for the morning...

i've disconnected the battery and we'll see in about an hour what the scoop is on the ecu reset.

thanks,
mike

#7 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 17 December 2008 - 01:26 PM

And there is your answer.


nipper

#8 frag

frag

    Soob shade tree mechanic

  • Members
  • 1,777 posts
  • Montréal, Québec, Can.

Posted 17 December 2008 - 01:56 PM

And there is your answer.

nipper


If you care to Nipper, I'd like to understand your diagnostic here.
How would the fact that his fuel pressure goes down to zero in two hours affect the starting hability of his car. Mine has always taken about the same time, maybe a little longer, to go down to nil and I have no starting problem.
Moreover, his fuel pressure with ignition on and with engine running seems, to me at least, sufficiently close to spec to have no adverse effect on starting.
What am I missing?
Thanks in advance for your answer.

#9 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 17 December 2008 - 02:55 PM

Thats where i would go next, if it was my car, He can have a leaking fuel pressure regulator that takes extra long to build pressure back up.

Lets do another Regulator test. Detach the vacumum hose from the regulator and watch the gauge. The fuel pressure should go up considerablly. If it doesnt go up check the vacuum to the regulator with a gauge.

Leak down is normal, but your not complaining of a cold start issue which sounds like to me his regulator is lazy and taking a while to allow pressure to build back up. Another test would be to pinch off the return line and look for a quick rise in fuel pressure, as this would rule out the fuel pump.

One other thing to look at, and i know its awfully cold to do this, is a compression test.

I forget have plugs been changed on this car?

nipper

#10 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 17 December 2008 - 04:06 PM

thanks for the responses once again,
here's more:

went out after an hour and hooked everything back up. Fuel pressure at 0, went up to 42 upon ignition on. Cycled ignition a couple of times. Started like always, 5 sec of cranking, catches a bit then finally idles well. turned off. Started again, less cranking and idles well. turned off. Started again, less cranking...and so forth. Did this 5 times and by the final time the car was starting in a second or so. Starting to make me lean toward fuel pressure issues?

While idling if i pull off the vac hose the pressure rises immediately and drops as soon as i hook it up, no delay what so ever. Normal?

Plugs were changed about 10,000 miles ago with the motor install and i'm guessing they were the fancy ones since the p.o.'s receipt shows $51.80 for the 4.

-mike

#11 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 17 December 2008 - 04:18 PM

The pressure response is normal.

Lets try one more thing tomorrow morning. When you get in the car first start, turn the car to on. count to five, then crank the engine see if it fires right off.


nipper

#12 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 17 December 2008 - 05:15 PM

i'll give it a shot tomorrow morning. thanks for all the help.
i have an appointment at the dealer in the morning but the car will be warm by then, do you think they'll be able determine anything that we haven't discussed here with their computers?

mike

#13 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 17 December 2008 - 06:10 PM

i'll give it a shot tomorrow morning. thanks for all the help.
i have an appointment at the dealer in the morning but the car will be warm by then, do you think they'll be able determine anything that we haven't discussed here with their computers?

mike


No your going to have to leave it with them and see it for themselves. They will hook up the Select monitor and fuel pressure gauges in the morning and will be able to see it better then us making educated guesses over the net.

nipper

#14 Stickboy42

Stickboy42

    New User

  • Members
  • PipPip
  • 10 posts
  • Moscow

Posted 18 December 2008 - 02:38 PM

well i feel like a potentially big idiot right now. on my list of simple things to check was the green service connector. well, forgot to check it and did all the other stuff only to have the dealer find out it was connected. The CEL is also burned out, hence no flashing CEL to make me wonder if it was connected or not. i sure hope the po didn't remove the cel because they didn't know about the service connector.

anyway, we'll see what it does in the morning for cold start and see if any codes are present then if the problem isn't gone away by then....

i'll keep you posted,
m

#15 nipper

nipper

    Semi Elite Master of the

  • Members
  • 17,634 posts
  • Long Island NY

Posted 18 December 2008 - 02:42 PM

And just how many lumps of coal are we going to send you?


nipper

#16 3Pin

3Pin

    Eat, Live, Breath Subaru

  • Members
  • 359 posts
  • Milwaukee

Posted 22 December 2009 - 10:48 PM

How did this turn out? I am battling the exact same issue now....well except for the green connector being connected.

#17 forester2002s

forester2002s

    Subaru Fanatic!

  • Members
  • 528 posts
  • Vancouver Canada

Posted 03 January 2010 - 07:15 PM

Bump.
Any answers out there.
My son has the same cold-start symptoms on his 2004 Impresa.

#18 Gloyale

Gloyale

    It's a sickness

  • Members
  • 9,479 posts
  • Corvallis, OR PNW

Posted 04 January 2010 - 11:17 AM

Coolant Temp sensors are the ussual suspect for cold start issues in my mine.

Though the OP in this thread states his was replaced.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users