Weird Knock Retard on F-150 Ecoboost

[check1222]

Hey y'all,
I have some weird looking knock retard with my 2011 f-150 ecoboost. At WOT I get up to +12kr and at low rpm I get high negative kr when I hold a certain position on the throttle. This is my second ecoboost engine for this truck and both have had this same issue. Happens on stock as well as all three tunes. Another thing I thought was weird was that the speed LoRes was picking up the same value as the Knock Control Spark Retard. Sorry for the bad data log, it started raining here.

Thanks

[mikel]

please post the files from the tunes folder ont he i2 drive as well.

[check1222]

I’m currently on a 2 week trip but I’m just using the can 91 tune from the trinity 1000 for the 2011 f150 3.5l EcoBoost. Will upload when I return.

[check1222]

I had been running the MPG Boost tune for my trip. I usually run the 91 octane tune and have just switched it back. Sorry for the late reply.

[DiabloMatt]

could things come to mind here. first of all are you running the updated plugs preferable a NGK 6510 with the gap closed down to .028? the fact that it does it on the stock tune bugs me. these were bad about the intercooler filling with oil and also the intakes filling with oil from the crankcase blowby. those are a couple things you could try first. i dont see anything wrong with the tune. i could always remove timing from the tune but that's going to make it a slug. does the knock go away if you run 93 octane on the stock tune? that will help rule out "false knock"

[check1222]

I have replaced the plugs with the new updated ones to .30 gap about three months ago and I have also drilled my intercooler as I have experienced the water in the intercooler bog before but this is different. I have recently found a small exhaust leak at the clamp directly after the left cat. Octane makes no difference as I only use 93 where I live and have tried multiple stations and locations. I do hear a weird deep hum from the engine when it adds a ton of timing. The timing also only seems to get PULLED when at speed and not from a stop (like the interstate to WOT).

[check1222]

Also reducing the global spark does not change anything nor adding more fuel to the rich/lean condition.

[check1222]

Sorry one more thing to add. I am on my second engine (turbo blew out on first engine) and It happened(s) on the stock tune with 93 octane on both engines.

[S4IN7]

I have replaced the plugs with the new updated ones to .30 gap about three months ago and I have also drilled my intercooler as I have experienced the water in the intercooler bog before but this is different. I have recently found a small exhaust leak at the clamp directly after the left cat. Octane makes no difference as I only use 93 where I live and have tried multiple stations and locations. I do hear a weird deep hum from the engine when it adds a ton of timing. The timing also only seems to get PULLED when at speed and not from a stop (like the interstate to WOT).

I'm having the exact same issue and have tried everything you've tried and more to no avail. I ALSO have the same leak around the clamp just downstream of the left/driver's side cat. It's gotta be related right?

When I get some time I'm going to replace that clamp and seal everything up again. I have a theory that the small leak is lowering back pressure sporadically and just enough to cause the O2 sensors or PCM to mess with timing/fuel.

Haven't been able to find anyone with the same symptoms as me on any of the major Ford and EcoBoost forums...I really hope you see this and we can figure it out!

[check1222]

Hm it’s nice knowing I’m not alone with this issue. I would think that some of those 4inch exhaust systems would have similar issues but you’ve convinced me to get it fixed next week. I think one of the million exhaust shops here could put a new clamp on or weld it so I’ll let you know if that fixes it. I’ve done a lot of research on this and some of the Thing I looked into were the knock sensors, spark plugs, etc. but after replacing my engine and plugs twice I think it’s either the exhaust or something is loose and making noise. My list is: exhaust, something else loose causing noise, wiring somewhere (I have also heard of one of the knock sensor wires chaffing against the engine causing issues).

Also: I don’t think it’s anything on the suspension that is loose or the drivetrain since I installed a lift kit after the second engine and everything under my truck is tight ; checked all the ballpoints, u-joints, mounts, etc.

And sorry for the unorganized post I’m on my phone.

[check1222]

Sorry for the second post,
But for your theory you might be onto something. At around 50mph to interstate speeds, if a use a light/constant throttle my engine will create a drone and the timing will advance for some reason to the max the gauge will read. This has gotten louder and within a larger range of peddle im guessing since the leak has gotten worse. My short term fuel trim has reached +30% in some instances as well. Will get the leak fixed and the o2 sensors cleaned and see what happens.

[check1222]

Okay good news. I think I fixed a majority of the kr issues. Today I cleaned all three MAF sensors. Only one that was dirty was the third sensor found above the engine, and man was it dirty. Used compressed MAF cleaner and a q-tip and got it as clean as possible then removed and cleaned my throttle body. It had a pretty thick light-colored coating on it (I assume from blowby?) Reassembled and tested WOT and maxed at 6kr the entire run with many WOT runs from 0-75 and 45-75mph. Most of the time a had 0kr at wot with an exception of a few runs picking up 4-6kr retard that quickly dropped.

MAF sensors require a trox wrench and a 6mm wrench for the third.
Throttle Body requires either a 8mm or 9mm I forget. Throttle body was a pita since my electrical connector was stuck on. Instead of breaking the clip (I’ve broken a few of these d**n things) I decided to just disconnect the tubes going to the air intake pipe going into the throttle body then I loosened the flathead clamp and removed the tube. After that it’s just a matter of unbolting the 4 screws holding in place and cleaning it. Assembly was much quicker then removal.

Hopefully the truck stays this way but with my ecoboost history I’m not sure. My guess is that the MAF was causing a lean or rich condition or something that caused the engine to pull timing at WOT. Lastly, I also threw in a bottle of Techron fuel injector cleaner but I don’t expect that to have any effects on my results. I’m also still having the timing advance at part throttle and the exhaust drone from what I assume is the exhaust leak’s fault.

Edit: Also did the throttle reset after cleaning (key trick).

[mikel]

good call on the MAF cleaning.