Ford Focus ST Forum banner
1 - 20 of 22 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 · (Edited)
My 17 with 72,000 miles has been misfiring bad (along with misfires as the car gets up to temp / warm up idling as well, usually 5-15 misfires) when I pass 5k rpm, it’s especially bad in 3rd 4th 5th on freeway. I believe this problem started about a two months ago and felt very minor then progressively got worse and worse. Brand new cold ngks at 026 and brand new oem coils aren’t the culprit. It doesn’t misfire when given partial throttle up to 6k which makes me think it’s fueling. Afrs up to 5k before it does it are 11.9ish, car is not boost or vacuum leaking, and car runs perfect until I approach 5k wot. I haven’t tried cleaning the maf sensor or injectors but that’s what I’m trying next, but I’m skeptical.
mods- turbosmart IWG actuator, (which I’ve recently heard may actually be a poor decision to run) injen intake, 3in catless into 3in awe resonated touring, cpe- 5.5in. Intercooler, boomba stage 2 catch can, ngk plugs. Tune - custom dyno tune by TurboLab. Other info - car is not throwing any codes and hasn’t for months.
About 8 months ago the purge valve did it’s thing and was broken for a few months but then ran perfect after replacing it, and the car was not doing this about 1.5-2 months ago.
Any thoughts or comments would be greatly appreciated, I’m running out of money for trying to spot guess what’s going on.
 

·
Super Moderator
2014 ST3. Garrett GTX2860R Gen 2. FBO
Joined
·
8,868 Posts
Can you share a datalog of this issue happening please? Upload it to Datazap and post it here.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #4 ·
Yes I’ve never taken one though so it’ll take me some time to get everything on my computer set up etc, I’ll go off 4th gear for it.
I’ll do it because I want to know what’s going on but I’m hesitant because I think it’s quite unhealthy for the car especially with my wastegate spring holding more boost up there.
 

·
Super Moderator
2014 ST3. Garrett GTX2860R Gen 2. FBO
Joined
·
8,868 Posts
I get where you're coming from and you are absolutely justified in those concerns. It's just there is no other way for us to properly help you from hundreds of miles away.

I mean. You'll have plenty of people throwing out possibilities, but you mentioned being at the end of the line as far as throwing parts. So for us to get a proper diagnosis we need proper solid data.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #6 ·
I get where you're coming from and you are absolutely justified in those concerns. It's just there is no other way for us to properly help you from hundreds of miles away. I mean. You'll have plenty of people throwing out possibilities, but you mentioned being at the end of the line as far as throwing parts. So for us to get a proper diagnosis we need proper solid data.
datazap.me | Ethan_st3 | map 11 Here is the Log, Let me know if there's anything else you need! I think I did it correctly. its a mid rpm pull in 4th up to about 54,5500 rpm where it did its thing.
 

·
Super Moderator
2014 ST3. Garrett GTX2860R Gen 2. FBO
Joined
·
8,868 Posts
So that was a bit messy, because you shifted to 5th before ending the log. I'm just saying this out loud for anyone else looking. There is a gear change here.

However. About 5000rpms, your ignition timing begins taking a dive and goes HARD negative. Everything else seems to be in order.

Try adding 1 gallon of e85 to the tank and top off with premium fuel so you're back up to a full tank. Then take another log. Trying to determine if this is a false knock condition or not.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #8 ·
So that was a bit messy, because you shifted to 5th before ending the log. I'm just saying this out loud for anyone else looking. There is a gear change here.

However. About 5000rpms, your ignition timing begins taking a dive and goes HARD negative. Everything else seems to be in order.

Try adding 1 gallon of e85 to the tank and top off with premium fuel so you're back up to a full tank. Then take another log. Trying to determine if this is a false knock condition or not.
I live in northern Utah and have zero access to e85, the nearest one is an hour away. Is there something else I can try / can you explain what a false knock condition / what it looks like is going on? also what do you think about the boost psi during the pull?
Thanks a ton for taking your time to help diagnose what you think is going on!
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #9 ·
I live in northern Utah and have zero access to e85, the nearest one is an hour away. Is there something else I can try / can you explain what a false knock condition / what it looks like is going on? also what do you think about the boost psi during the pull?
Thanks a ton for taking your time to help diagnose what you think is going on!
just remembered this - I believe the issue started occurring around when i tried using cobb FFS from the accessport, but I'm not sure if that has anything to do with it, and I do not flat foot shift, I just played with the settings, which reset every time the car is turned off.
 

·
Super Moderator
2018 Ford Focus ST1 with a 2867 gen 2
Joined
·
2,446 Posts
I live in northern Utah and have zero access to e85, the nearest one is an hour away. Is there something else I can try / can you explain what a false knock condition / what it looks like is going on? also what do you think about the boost psi during the pull?
Thanks a ton for taking your time to help diagnose what you think is going on!
Toluene and xylene are chemicals you can buy from Sherwin Williams/Lowe's/Home Depot and add to the tank to get the octane up a bit, too... WAY more expensive than e85, but likely more readily available for you. Just did a quick search and a gallon of xylene from my Lowes is $25.

For what it's worth, both are used as "octane boosters", and if you look at the ingredients list of an octane booster bottle, one or the other is usually the primary ingredient.

From memory, I think both of those have an octane rating around 114, and they have a similar stochiometric ratio as gasoline, which e85 doesn't. 5 gallons of 91 + 1 gallon of 114 would give you an overall ratio of 94.83, but then again, use at your own risk...

Just because I used to run a gallon of it in a tank of fuel on my Dakota doesn't mean you should, but it always worked for me...

Fwiw, false knock is the engine computer thinking that the motor is having pre-ignition on a cylinder or multiple cylinders and pulling timing accordingly to help combat that, but in reality, there's no true pre-ignition. Silly question, but when you fill up, are you typically topping off when you only need 1/2 a tank or less, or are you running it down to just a couple gallons before your fill up? Reason I ask is because if your stations are like mine, that pump for 91 shares a line with 91, 87, and 85 octane fuels. If you're only putting in a few gallons each time, you're most likely getting at least 1 to 1.5 gallons of 85 in every fill up, and over time that's going to drop your octane of fuel in the tank into the 88 octane range, which is going to suck for detonation/pre-ignition resistance.

Run the tank down low (50 to 60 miles left) and fill it with some Exxon/Chevron/anything but Shell 91 and see what happens with a data log.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #11 ·
Toluene and xylene are chemicals you can buy from Sherwin Williams/Lowe's/Home Depot and add to the tank to get the octane up a bit, too... WAY more expensive than e85, but likely more readily available for you. Just did a quick search and a gallon of xylene from my Lowes is $25.

For what it's worth, both are used as "octane boosters", and if you look at the ingredients list of an octane booster bottle, one or the other is usually the primary ingredient.

From memory, I think both of those have an octane rating around 114, and they have a similar stochiometric ratio as gasoline, which e85 doesn't. 5 gallons of 91 + 1 gallon of 114 would give you an overall ratio of 94.83, but then again, use at your own risk...

Just because I used to run a gallon of it in a tank of fuel on my Dakota doesn't mean you should, but it always worked for me...

Fwiw, false knock is the engine computer thinking that the motor is having pre-ignition on a cylinder or multiple cylinders and pulling timing accordingly to help combat that, but in reality, there's no true pre-ignition. Silly question, but when you fill up, are you typically topping off when you only need 1/2 a tank or less, or are you running it down to just a couple gallons before your fill up? Reason I ask is because if your stations are like mine, that pump for 91 shares a line with 91, 87, and 85 octane fuels. If you're only putting in a few gallons each time, you're most likely getting at least 1 to 1.5 gallons of 85 in every fill up, and over time that's going to drop your octane of fuel in the tank into the 88 octane range, which is going to suck for detonation/pre-ignition resistance.

Run the tank down low (50 to 60 miles left) and fill it with some Exxon/Chevron/anything but Shell 91 and see what happens with a data log.
Thank you for that input but I don’t believe that is the cause. Most of the time I run the tank till the gas light comes on, and I fill up with Smith’s (grocery store) gas which has known high quality. I can still try though. Do you think it’s worth reaching out to the shop that tuned me? I also plan on emailing this log and the explanation of my problem to stratified for them to look. Idk man.
 

·
Super Moderator
2014 ST3. Garrett GTX2860R Gen 2. FBO
Joined
·
8,868 Posts
Yeah this is the crossroads we are at. Some sort of octane booster is needed here to determine if we're chasing false knock or real knock.

You do say you always fill up at the same place. Something else you could do is drive this tank easy, and fill up with premium fuel from another top tier station. See if the fuel change makes a difference. It's possible this particular store got a subpar batch of fuel or someone screwed up and didnt pump premium into the premium tank upon delivery of the fuel.



I also meant to mention that thanks to the TS wastegate actuator you are still pulling 20psi at the top of this log which is way too much. With the k03 boost should peak in the midrange and then decrease toward redline, about 13psi at 6500rpm. Reason being is the turbo is SO far past it's efficiency, spinning it any harder just turns that turbo into a tiger torch. Also creates some extreme back pressure on the exhaust side, which can cause an issue like this to pop up if you get a batch of subpar fuel.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #13 ·
Yeah this is the crossroads we are at. Some sort of octane booster is needed here to determine if we're chasing false knock or real knock.

You do say you always fill up at the same place. Something else you could do is drive this tank easy, and fill up with premium fuel from another top tier station. See if the fuel change makes a difference. It's possible this particular store got a subpar batch of fuel or someone screwed up and didnt pump premium into the premium tank upon delivery of the fuel.



I also meant to mention that thanks to the TS wastegate actuator you are still pulling 20psi at the top of this log which is way too much. With the k03 boost should peak in the midrange and then decrease toward redline, about 13psi at 6500rpm. Reason being is the turbo is SO far past it's efficiency, spinning it any harder just turns that turbo into a tiger torch. Also creates some extreme back pressure on the exhaust side, which can cause an issue like this to pop up if you get a batch of subpar fuel.
I agree. I’m ashamed I didn’t do enough research on the wastegate actuator, I was hungry for more power without BT, and have just recently learned that the k03 gains almost nothing at the higher rpm’s and only a little in the mids. is it possible to get a different tune (even though it’s an upgraded IWG) to make it drop off to like 14-15 psi in the higher rpm’s?
i should also mention that my car Misfires a lot on cold start up and getting up to temperature, usually around 5-15 misfires until it’s warmed up, then a misfire every couple of minutes of soft driving. But when I floor it let’s say third from 3-4K rpm, no misfires for the small pull.
I’ve read your other replies to some similar threads, should I run a compression test as well?
I’m headed out of town for the holiday so I won’t be able to test anything for a couple of days, but I will be contacting lots of places for more info.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #15 ·
Like @TurboGT said: boost too high at the top rpm, how long had been like that? Get a compression test before throwing more money into it.
It’s been like this for probably 8-10k miles. The tuning shop I go through said it wasn’t a big deal and that lots of focuses do it for more power up high. I am most likely going to get a different tune from stratified or JST that will taper it off to 15 again.
 

·
Super Moderator
2018 Ford Focus ST1 with a 2867 gen 2
Joined
·
2,446 Posts
I’m surprised you can reach over 20 psi at top end with the small snail.
Yeah, that thing has got to be so far out of it's efficiency range that it's more like a heat gun than a turbo.

Whoever your "tuning shop" is that said a STOCK turbo is ok to run 20 psi at the top of the rpm range is on drugs. With a 2860/2867/g25? Sure. That's designed to do that. The piddly little k03? Not hardly.

Dump that tuner like a bad habit and go with somebody who actually cares about the motor's internals not becoming externals.
 
  • Like
Reactions: STallion18
1 - 20 of 22 Posts
Top