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2005 Forester XT 4EAT
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Discussion Starter #1
This is a weird issue that i can't seem to figure out on my own and most of the people i've talked to are stumped. First thing in the morning my car fires up quick, and when the car is warm it usually starts up quick with a stumble before idling up. If i let the car sit for an hour or so it takes forever to fire up. Cranks for almost 4 - 5 seconds sometimes.

I've been intermittently pulling a code, P0301 Misfire Cyl-1. So last night i went ahead and changed the plugs on Cylinders 1 and 3 as well as switched the coil packs to see if the misfire code would follow the coilpack to a different cylinder. As it happens this morning the car started up and was idling and i'm pretty sure i felt it missing, but it didn't throw a code, if i pull a new code later i'll post up.

Also I forgot to mention, the plugs i pulled out were only 15 - 20k old, and were in very good shape.
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #2
Still got a Misfire code for Cyl-1 ... So now it's either i got a bad injector or a bad plug wire/injector wire...
 

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2005 Base 2.5x foz
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896 Posts
If you have a DMM (volt meter) check power and ground for the injector. If you have a osciliscope check for a good injector waveform!
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #4
I think i may end up pulling the injector and taking it to a local place that does injector testing/services and have them put it through all the tests to see if it's leaking or something.
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #5
It's definately gotta be an injector, this morning with the extreme cold i was only firing on 3 cyl's majority of the way to work and the 4th cylinder would only kick in at 50% or more throttle. I think the injector is just stuck open and when i give it more gas the extra spark gets the fuel burnin again.
 

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2016 Forester XT Premium CVT
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757 Posts
have you replaced your injectors are they stock?

You may have a cut O Ring on the bottom of the injector leaking fuel straight from the fuel rail down into the intake ports.....

or, as you said, a sticking fuel injector.....
 

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Smooshed FOTY 2011
2005 Lifted 2.5 XT 5-Speed MT Dual-Range
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5,813 Posts
I doubt it's your injector, honestly. Unless you've been putting crap gas in your car (which I take it you haven't), odds are your injectors are fine. Best way to check is swap injectors for another cylinder and see if the misfire continues on that cylinder. If it does, it's not your injector. (I've never had luck with a shop being able to successfully test an injector.....unless of course it just wasn't working, which is rare)

To be 100% straight forward with you, my old engine was doing almost the exact same symptoms as you are describing before I ultimately found out that it needed to rebuild it. (down to the point where you knew it was misfiring, but wasn't throwing the code)

Swap injectors and see if the misfire continues. If it does in the same cylinder, take the car to a trusted shop and have them perform a compression AND a leak down test. The compression tests compression of course, the leak down will see if the cylinder leaks at all. From there, if one of your cylinders is off-par, you can go into further inspection to see if it's a disintegrated ring or if you simply just need a valve job.

Now, I'm of course describing the worse case scenario.......and it could be something simple. I'm just stating that your symptoms were almost exactly what mine were before the **** hit the fan.

Good luck man, let us know of what you find out.
 

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2004 Forester XT
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8 Posts
My HS shop teacher always to start with something easy. Swap the plugs (or just get new ones) and see if the problem moves. Plugs can look good and not be good...

You can also look for any issues in wiring between the coil packs and the ECM. Worth a shot...

Good luck.
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #9
I've tried plugs, and i've tried swapping the coil packs around, no luck. The only thing left is an injector or wiring issue, or worst case scenario an internal issue. But that fact that i have side feeds modded to 830cc makes me think an injector is most likely the issue.

Up until just the other day which was the coldest day this season, the car ran fine above idle, i hit/held target boost, and all 300hp is definately still there. I have a feeling that 14 degree night literally froze the injector open, or if it's an O-ring issue, the O-ring was shrunk so bad it was just letting fuel pour in.

I'll see what happens monday when i pull the injector.
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #10
Leaky injectors FTL! I watched my injectors in the flow/leak test, and it was really just plain sad. The spray patterns on all of them were not the best, and they all dripped a little fuel on the leak test except for the cyl-1 injector which poured out fuel like it was a tap.

I can safely say i would never recommend witch hunters to anyone. I just had to drop $600 on some DW 850's that will hopefully perform as advertised.
 

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2005 Forester XT 4EAT
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2,185 Posts
Discussion Starter #13
Just got my new DW's in the mail, and it's pretty clear to see why DW gets $599 for their injectors, and places like witchhunter are so inexpensive... Everything about the DW injector is cleaner and more solid.

Heres some Pics:








DW's on the left
 

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2005 forester xt
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82 Posts
I am having similar problems on my Cyl 4, is replacing the injector any harder than replacing the plugs? Also, i would just assume go with stock injectors but if there is no disadvantage to going up size (600-700) just to be ready for a future tune (fingers crossed) I would very much do that. Are injectors on/off or are they variable, delivering only the amount of fuel needed. to put it better, will larger injectors suck extra fuel for no appreciable benefit? Lastly, where can i get good replacement injectors?
 

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2005 forester xt
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82 Posts
CYL # mixup

I just replaced an injector in my FXT but It might have been put in the wrong cylinder. Is the cyl order this



or this

 

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05 FXT
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1,540 Posts
You're right in both senses...

Injectors are just on and off.

However they turn on and off at high speed, and that's how the amount of fuel dumped in is controlled.

You WILL need a tune if you go to bigger injectors than stock. If the person tuning is competent, than no, it should not hurt your fuel mileage, well, significantly enough to matter.
 

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2004 2.5 FXT manual
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7 Posts
How would it run without a tune and bigger injectors? Rich I guess but if they are open for the same amount of time as the stock injectors with the stock fuel pump will it be noticeable?

I need to replace the injectors but Im not ready to do a full build.

Plus four 850cc DWs are only $80 more than stock replacements from parts store.
 
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