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15 Fist OAR and knocks

Messages
7
Likes
1
Location
Tbilisi, Georgia
#1
Hi friends. New owner of Fist and i love it. It has 34k miles. Previous owner gave me AP with the car and i never plugged it in before. When i plugged my suffering started :)

All the time i am watching it.

When i plugged it in first time i saw it had stage 1 map and it had one gauge of knock detected and it showed few times 0/1. OAR was showing -1.0.

Car is fully stock and my friend told me its because of it. And told me to switch maps. I switched to stage 1 with 93 and with one 3rd gear pull i got 2 knocks per 1st or 4th cylinder i dont remember which one.
Then i tried stage 0 and knocks almost disappeared. I hardly get one per day but OAR shows now -0.75. As i know it must be -1.0

Someone tell me what to do? I dont want to kill the engine. This is the best car i have ever owned. I love it very much
 


Rocketst

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#2
Oar should be at -1. That's your octane adjust ratio, means your running 93. Knock sensors in these cars are extremely sensitive it could actually be drivetrain issues that are causing your knock and are not actually a problem or it could think there's a knock when there isn't one. These cars also knock and misfire a lot. As long as your not getting a code your fine. If you would like to do your deligence, check spark plugs gap is correct and that you have oil in the car and your coolant is topped off and your brake fluid is full as well. If all that's correct your cars running fine. Don't pay too much attention to data, the car will tell you if it needs your attention.

Sent from my moto z4 using Tapatalk
 


Rocketst

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#4
Also, getting an intercooler upgrade would greatly improve your tune above stock. Your cars probably knocking because it can't handle the temperature increase of the increase in timing.

Sent from my moto z4 using Tapatalk
 


Rocketst

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#5
Yeah. Anything more than -1 usually indicates bad fuel. Try a different pump. When you find one that is -1 stick to that station. Avoid offbrand stations.

Sent from my moto z4 using Tapatalk
 


MagnetiseST

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Dania Beach
#8
Thanks for fast reply!

So -0.75 means fuel octane is too low?
Also be aware that anytime you re-flash the car, it needs to learn the OAR again. Also anytime you get gas, it will likely do a bit of a re-learn. The rule of thumb for tuning is to let the car get to -1 before doing a datalog.
 


Ford ST

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Pleasant Garden
#9
Last edited:
OP
N
Messages
7
Likes
1
Location
Tbilisi, Georgia
Thread Starter #10
Guys i changed maps from AP few times yesterday. Also tried different fuel and ECU reset from AP. And OAR dropper to -0.75 from -1.0. I just want to get rid of these knocks.

Using stage 0 at the moment
 


Messages
160
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99
Location
Cheshire
#11
Have custom tune from Mountune for stage 1 93. I have a bad gas map on slot 4 that I switch to if AOR is higher than 0.95. I usually do a pull after each fill up to check the if the gas is at -1
 


Messages
309
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Location
Brooklyn
#12
Guys i changed maps from AP few times yesterday. Also tried different fuel and ECU reset from AP. And OAR dropper to -0.75 from -1.0. I just want to get rid of these knocks.

Using stage 0 at the moment
Can't really get rid of all knocks. You can try to reduce the chance of them by adding octane or run the stage one 91 map while using 93 fuel.

DEss
 


M-Sport fan

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Princeton, N.J.
#14
Is your avatar location accurate at all??

IF so, does that area of the world get the US/North American spec MAP based tune FiSTs, or the Brit/Euro/rest of world MAF based tune ones? [dunno]

IF the latter, the AP should not work AT ALL on your car (is it a 2 DOOR?), and could be the root of your problems. [???:)]
 


OP
N
Messages
7
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1
Location
Tbilisi, Georgia
Thread Starter #15
I have american Fist imported here.

Today i added 15 liters of our best brand fuel in my old one which was showing 60 km until empty and tried some wot pulls on highway. First pull made only one knock on cyl 1 and other ones did not show anything. And car felt so much faster!

That fuel is called euro 98 on the station. The most expensive one. And weather was colder too on evening. I think warm weather and bad fuel caused that knocks??? Who knows
 


JDG

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Conshohocken, PA
#16
Hi friends. New owner of Fist and i love it. It has 34k miles. Previous owner gave me AP with the car and i never plugged it in before. When i plugged my suffering started :)

All the time i am watching it.

When i plugged it in first time i saw it had stage 1 map and it had one gauge of knock detected and it showed few times 0/1. OAR was showing -1.0.

Car is fully stock and my friend told me its because of it. And told me to switch maps. I switched to stage 1 with 93 and with one 3rd gear pull i got 2 knocks per 1st or 4th cylinder i dont remember which one.
Then i tried stage 0 and knocks almost disappeared. I hardly get one per day but OAR shows now -0.75. As i know it must be -1.0

Someone tell me what to do? I dont want to kill the engine. This is the best car i have ever owned. I love it very much
Take a look at Stratified's blog. This post in particular answers all of your questions and will give you a better understanding of knock detection in the ecoboost (knock is not always synonymous with bad):

http://stratifiedauto.com/blog/how-the-knock-detection-system-works-in-the-ecoboost/
 


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