Anyone want to look at my LOGS?

Hey guys glad to be back... sorta... recently when i go full throttle, or even near it and get over 5 or so psi, the car breaks up badly and goes no where. on stock tune its not nearly as noticeable but the car definitely feels a little sluggish. I've attached one of my good pulls from when i was in the process of getting an E-tune, marked "full pull 3 rev 3", and couple of logs from since I've had the problem. the newer logs may or may not be useless, and but I'm quite willing to take a few more if anyone has specific driving conditions that they think would help show the issue, or want different things to be logged. I've tried to contact Mcdowell tuning, who i got the tune from, but i don't think he's in the biz anymore since his website is down and he didn't answer any of my emails. any help is much appreciated.

Thanks, STIK

full pull 3 rev 3.csv

datalog25.csv

datalog24.csv

datalog23.csv

datalog22.csv

datalog21.csv

Starting to think its a bad coil, i had one go out on me 2 years ago and i got similar signs as what i saw before it went completely, just random little blip where it feels like i closed the throttle completely for a split second. which turned out to be it missfiring (cylinder 3 i think) though i never got any codes until it died completely. I'm going to keep my fingers crossed it has a weak spark this time around and thats why it can't handle boost. because changing the coil packs and spark plugs would be relatively easy. is there a way to test coil packs with a multimeter to know if it's good?

You could log all cylinders for misfires. Even though the ecu isn't giving you a trouble code during cruising around it'll still keep track and you could log.

thanks shadow, I'll add misfires to the logged parameters and see whats what tomorrow.

i checked this morning on my way in but couldn't find anything with "misfire" in the loggable parameter. does it have some kind of funny name?

I believe it is knock sum...or something around that name, possibly also called cylinder roughness.

I believe it is knock sum...or something around that name, possibly also called cylinder roughness.

 

knock and misfire are not the same, cylinder roughness i did see tho....

 

just checked and cylinder roughness is a misfire count... thanks FL

You're probably going to see cylinder 2 a little higher than 1 and 3, and 4 will be pretty substantially higher, which is because the sensor is on top of cylinder 4, so it's a little over-sensitive to events on #4, and on #2 to a lesser degree. 1 and 3 should be about equal, so if either of those is significantly high, that's where I'd start looking. Last time I tried chasing something like that (turned out to be nothing, coils are all good), I was seeing something like 4, 10, 4, 40 for cylinder 1-4 knock count. Swapped 3 and 4 plugs and coils, no change.

yea my cylinder 4 knock count has been through the roof since day 1. i can get it to register one just by tapping the engine cover. i don't look at it or track it anymore cause it gives my freakin agita to see it constantly count up. you're saying I'll see a similar pattern with the cylinder roughness (misfire) count?

Hey there,

 

I agree that if its breaking up during acceleration that would more likely be a bad coil/plug or gummed up injector but most likely plug or coil.

 

The parameter that will show misfires is roughness counts cyl 1,2,3 and 4.

 

The stock mapping would have less issue due to less load on the engine but still should do it at close to the same boost levels if your only getting 5-6psi on either before the issue starts happening.

 

Hope that helps.

 

Dave

Hey there,

 

I agree that if its breaking up during acceleration that would more likely be a bad coil/plug or gummed up injector but most likely plug or coil.

 

The parameter that will show misfires is roughness counts cyl 1,2,3 and 4.

 

The stock mapping would have less issue due to less load on the engine but still should do it at close to the same boost levels if your only getting 5-6psi on either before the issue starts happening.

 

Hope that helps.

 

Dave

It does, thanks! i just went to get lunch and logged roughness for all cylinders. saw 1 on cylinder 2 and a ton on cyl 4, enough to set off a p0304 if i grit my teeth and leave my foot in it. so i've at least located the misfire. subaru dealer by me (read worst dealer ever) doesn't have any coils on hand so they will have to wait but I'm going to grab some new plugs and toss them in tonight see if it persists, and order the coils in that case.

 

whats are your opinions on replacing a coil that has had a bad plug in it? the pessimist in me wants to just get new coils and plugs all around to be sure i won't be back in there soon

If you have to order parts, it may be wise to also order one of these:

 

https://www.amazon.com/DEPSTECH-Semi-rigid-Inspection-Waterproof-Adjustable/dp/B00STB0EW6

 

The number 4 piston is pretty well known for being the problem child in the EJ25.

If you have to order parts, it may be wise to also order one of these:

 

https://www.amazon.com/DEPSTECH-Semi-rigid-Inspection-Waterproof-Adjustable/dp/B00STB0EW6

 

The number 4 piston is pretty well known for being the problem child in the EJ25.

 

idk I'm terrified at what i might find

If you have to order parts, it may be wise to also order one of these:

 

https://www.amazon.com/DEPSTECH-Semi-rigid-Inspection-Waterproof-Adjustable/dp/B00STB0EW6

 

The number 4 piston is pretty well known for being the problem child in the EJ25.

 

I have one and wasn't very impressed with the quality of the picture and the attachments suck at staying on. Ymmv.

 

I had two coil packs that started rusting and giving me problems. I replaced with used pulls from a 2016 sti

I would personally swap coils and toss a new plug in each cylinder while you are in there...easy quick diag to see if the code jumps/roughness jumps. *edit swap 2 to 4, not replace new quite yet*

 

Dave

Double, triple check the plug gap as well 0.028-0.031

Can you spot the bad coil? Look closely....

I can't get one off Amazon for over a week. Dealer will probably be 2-3 days and over charge me $30 dollars. Anyone know who produces the OE unit? Maybe I can get one at an auto parts store.

 

Sent from my Moto Z (2) using Tapatalk

Oe is something like Diamond electric. Maybe you can get something from a dealer on eBay quicker

Oe is something like Diamond electric. Maybe you can get something from a dealer on eBay quicker

 

that was a good thought but i just checked they all seem to give a delivery of next tuesday as well. I'm going to call the dealer tomorrow and see if i how far i can get the price down, and what their delivery date is and see if I'm willing to take the hit.

http://i.imgur.com/5856VDE.jpg

 

This was one of the ones I had to replace

update: Got a new coil pack and plug into cylinder 4 last night. and I'm glad to say she is back to normal. thanks for all the help guys. ended up using a deep 3/4 socket over the back of the spark plug socket to do most of it. the plug was in just as rough a state as the coil. it almost looks like someone used anti-seize or something and it burnt up because it backed out hard the whole way but i i didn't get any decent pictures of it maybe i'll post some tonight

Glad it was something easy and simple to track down.

glad it was a coil and not something bigger!

 

Dave