Subaru 2.5L E85 spark plug part number?

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sddoublee

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New to the Subaru world and E85 and I don't know who tuned the engine originally.  This car is a pig to start cold, we have had it for about a year now.  I looked up the plugs for a 2000 subaru outback and it doesn't match what I pulled out, which are ZFR7F-11.  I think it was O'reilly's website that says the gap should be around 44.  The plugs I pulled out look like they were purposely gapped narrower.  So any guidance on plug part number and gap would be great.  I'll start there to make this run better.

 
We have plenty of Subarus in our group, I have one in mine. Every single one is extremely cold blooded. Add E85 to the mix and its even worse. I had to start my rail the other day to re organize the garage. 30 degrees here in Utah. had to learn the "cold correct throttle position" to start, otherwise i would drain the battery letting it try lol. Subarus are great powerhouses, but worse than a lizard, if you know what I mean. 

 
What is approximately the throttle position you start it with?  We haven't found it, just crank and crank and crank and crank until it will sort of idle long enough so you can hit the throttle.  I am curious about the part number for the plugs too.  It looks like someone intentionally gapped the plugs tighter than they should to try to compensate for something.  

 
Plug gap is important on this turbo charged engine. The gap is set close as high boost can blow the spark out so to speak. Tighter gap keeps the spark clean and hot. If I recall its in the low 20's on the gap.

I dont remember the plug number.  NGK I believe.

Put a Nickel between the throttle arm and the stop set screw. Don't touch the gas pedal. Crank and let it start and warm up. Thats about all the throttle you need to help with the cold start.

Most if not all E85 Subis are a biatch to start cold. Just the way they were tuned back in the day.  A can of starting fluid is your friend. A small blast at the air filter will get it fire up at least once. I often let it sit for a min or two before I try and restart. Let the engine heat soak for a bit.

IMO newer tuning technology (ECU's) with open loop measurements and self learning can help as well as a good tuner.  Just takes more money and time if you want to try and help that cold start. :makerain:

 
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Holy cow! 44, as in .044? That is the same plug I run in my turbo Suby, but more like .022-.024 gap. I am duning right now, in Oklahoma. I run E85, Haltech ecu (I know, everyone out west hates them!) tuned by Wichita Dyno. It was 27 degrees F. this morning, and it fired right up and idled just fine. No special procedure. The afr was appropriately 10.2 until warmed up, then 14.5.

 
I should add that my boost limit is about 13 psi. 

 
I only have the 2.0 turbo but was told to use the ziptie trick and it totally works for me that is the throttle position that will start the motor quickly, once it warms a bit take it out and it will idle perfect, but my plugs are different they are ZFR6F-11 NGK V-Power

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I am sure John will chime in and set things straight 

 
ZFR7F-11, gapped at < .025.  Got it.  I'll replace them and see what happens and try the nickel/ziptie trick on the throttle.    

 
I use to do exactly what ESCO did , I actually set it up in a way that once i tapped the throttle after the motor was warm the tie wrap would drop by itself but always was attached to the motor so i didn't have to find a tie wrap every morning. On my new motor the tuner took his time and solved that hard cold start issue and it just starts and idles no matter how cold it is. Not sure what he did exactly , but it starts as good as my chevy diesel or my Toyota FJ.  Try the tie wrap trick it works great. I don't run E85 but I heard it does make cold starts harder. Good luck.

 
Reporting back to what I found.  Removed the original plugs and they were gapped at around .028" to .032".  Checked the compression which was around 150-160 in all cylinders.  Assuming that's good.  Pulled the new plugs out of their boxes and they were gapped at around .040 to .044" so I narrowed the gaps to right at .025" and installed.  Tapped the starter and it started right away and died.  Did that about 10 times before I was able to get it to start and stay running.  Still popping a bit out the exhaust revving it in the garage.  Would like to drive it and feel like it needs to be just run.  Noticed the radiator fans come on around 165 degrees, which I feel is a little early but I would like to know what you all think about that.  When I finally got it to take some throttle without dying out, I just put my hand on the pedal and slowly pushed until it ran reasonably well enough to sit there and idle.  Wondering if it's bad to let these things sit and idle until they warm up too.  Anybody can chime in, I am about 50-60% confident in bringing it to the dunes to see what happens or if I need to take it to someone that knows a hell of a lot more than I do on these E85 Subaru's.  

 
Also the zip tie trick to open the throttle did not help at all....

 
I have let all my subi cars warm up. Heck Ive even let them get to the point the fans come on. Do it in the summer months when not using the car as well just to run fuel thru the injectors

 
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