F150 Ecoboost Forum banner

1 - 18 of 18 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
Hey guys, I'll skip to the punch line: my Throttle is closing repeatedly starving the motor of air and boost, but looks like it WANTS to do this??!!

mileage: 245k
New plugs and coils (I replace them every year)
Phasers/chains/VVTs changed.
No codes, but my FORSCAN Data shows the Throttle being commanded to do what it is doing, so I'm stuck. You can hear the sound of the air being cut off from the boost... under wide open throttle it does get past it and take off, just moderate throttle makes it impossible to tow a 6k lbs boat. Any thoughts?
172290
1620589079941.png

172291
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #2 ·
I should add I checked the BOVs (2011-2012 don't have the same issues the 2013+ do..., but I pulled them and checked them anyway. Basically, we can see the truck still has boost, it's just getting cut off from the intake...
 

·
Premium Member
Joined
·
3,109 Posts
Have you ruled out the throttle body?
 

·
Premium Member
2013 XLT 302A 145" Screw
Joined
·
3,220 Posts
Change that TB out with new OEM.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #6 ·
Interesting..., I thought about changing the Throttle Body, but when I saw the actual position was following the desired position... I figured it was the pcm commanding it. And I have been hard pressed to find out the logic/parameters the pcm uses to determine desired position. Anyone know what logic the pcm uses and/or sensor conditions or parameters that used to determine desired postition?

*I realize the answer could be "dude, your throttle is not supposed to do that--change it"... but curiosity got me, and I hate throwing parts. So I believe you all, but I thought I'd ask anyway. Truth be told, I had it at a shop for a week and they told me to come pick it up...they couldn't fix it. I was shocked, I turned wrenches for 15 years and never let a vehicle go that I didn't figure it out. So I ordered the connector and downloaded FORSCAN so I could take a look... I got to the funny throttle behavior in a couple hours, but I wish I could confirm it before buying a part.

I'll check back in a couple hours, and if nothing else, I'll pick up the TB tomorrow and let you all know.

Thanks for the input,

Jeff
 

·
Premium Member
2013 XLT 302A 145" Screw
Joined
·
3,220 Posts
With that many miles, I'm surprised the TB hasn't been replace before now.
Also, have you cleaned all three intake sensors ?
 
  • Like
Reactions: RyEcoBeast

·
Registered
Joined
·
2,149 Posts
Interesting..., I thought about changing the Throttle Body, but when I saw the actual position was following the desired position... I figured it was the pcm commanding it. And I have been hard pressed to find out the logic/parameters the pcm uses to determine desired position. Anyone know what logic the pcm uses and/or sensor conditions or parameters that used to determine desired postition?

*I realize the answer could be "dude, your throttle is not supposed to do that--change it"... but curiosity got me, and I hate throwing parts. So I believe you all, but I thought I'd ask anyway. Truth be told, I had it at a shop for a week and they told me to come pick it up...they couldn't fix it. I was shocked, I turned wrenches for 15 years and never let a vehicle go that I didn't figure it out. So I ordered the connector and downloaded FORSCAN so I could take a look... I got to the funny throttle behavior in a couple hours, but I wish I could confirm it before buying a part.

I'll check back in a couple hours, and if nothing else, I'll pick up the TB tomorrow and let you all know.

Thanks for the input,

Jeff
I think the issue with the TB's going bad isn't so much that they stop working, it's that they no longer have the proper trim, so the positioning isn't accurate.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #9 ·
@Arkansas Eco ... I cleaned all Boost/MAP sensors with electrical parts cleaner, and all look good and inline with pcm baro reading KOEO. That was my first thought as well... boost sensor at TB does spike over desired momentarily, but that is at the same time the TB closes, and wastegate duty cycle picks up momentarily right after to correct... so I think that function is normal--just lags a bit (and I mean millisecs... but I'm not sure what data/refresh rate is on FORSCAN. The sensor at the air cleaner barely moves below baro... and air filter is new (replaced with the phasers).

I also pulled the pins on the TB boost sensor connector and checked resistance while tugging at wires... I saw a TSB for an issue there... no dice (also the readings seem normal).

@DNA Dan ... That makes sense... This problem has existed for awhile only slightly--but not bad enough to spend time on (I could still tow a boat without issue). When I did the phasers I cleaned the TB--that was prob a mistake since it was original :) I was careful and put the cleaner on the rag and didn't spray directly in the TB... oh well. It wasn't until you said that about positioning being inaccurate that I thought "...I probably should have left that alone..." Within 3 weeks of the phasers, it has gotten bad--happens almost every moderate acceleration now. (For anyone wondering--the phaser/cam timing was the 1st thing I check when laptop was hooked up.)

Part in stock at dealer, I'm picking up tomorrow and will let you know...

Thanks again, guys! **and for anyone who is looking--that FORSCAN program is pretty good. I wish I could overlay selected graphs... if the devs are reading, put that in the requirements for the next update.

Thanks,
Jeff
 

·
Premium Member
2013 XLT 302A 145" Screw
Joined
·
3,220 Posts
You've ruled out condensation in the CAC ?
 

·
Premium Member
Joined
·
1,428 Posts
The stock tune oscillates the throttle body when driving. It’s not like a standard NA application where the throttle angle correlates with the pedal position. Ideally the truck would throw a code for the throttle body if the positioning is wrong.

If you believe the throttle body is at fault, you need compare Throttle Angle Desired vs Throttle Angle Actual. That will let you know.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #13 ·
The stock tune oscillates the throttle body when driving. It’s not like a standard NA application where the throttle angle correlates with the pedal position. Ideally the truck would throw a code for the throttle body if the positioning is wrong.

If you believe the throttle body is at fault, you need compare Throttle Angle Desired vs Throttle Angle Actual. That will let you know.
I did compare them, and they match... replaced anyway on the consensus of others... graph of dsd and actual pictured above...
 

·
Premium Member
Joined
·
1,428 Posts
I did compare them, and they match... replaced anyway on the consensus of others... graph of dsd and actual pictured above...
I was going to mention, if the graphs aligned, then it’s not the throttle body. My mistake for not replying sooner.

Have you checked the boost solenoids above either turbo?

If you can, look at your OAR and Knock Sensor readings.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #15 ·
I was going to mention, if the graphs aligned, then it’s not the throttle body. My mistake for not replying sooner.

Have you checked the boost solenoids above either turbo?

If you can, look at your OAR and Knock Sensor readings.
I checked them last week, they seemed fine, but were so cheap and in stock, that I went to the dealer and picked them up and installed... keeping the truck for awhile... that seemed like a reasonable move. I will say it idles SO much smoother with the new TB though. Haha. At almost 300k miles, most things are maintainance at this point.
Talked to a service writer and drivability tech today, told him to clock on, fix it , and bill me. Gave them a $2k preauthorization to make it work, he’ll get on it.

I will post fix, I hope it isn’t the cac... that would make me feel silly for not pulling it again... been years since I did that—maybe the whole is clogged... more to follow. I’ve got a job, and am taking family out on boat this weekend... no time to waste anymore. Sigh
 

·
Premium Member
Joined
·
1,428 Posts
If anything, it wouldn’t hurt to check the WG solenoid on the top of the manifold. That T’s down to both wastegates which are actuated via boost not vacuum.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #17 ·
If anything, it wouldn’t hurt to check the WG solenoid on the top of the manifold. That T’s down to both wastegates which are actuated via boost not vacuum.
Changed all 3 solenoids... waste gate and bov... in the graph above ... shows wastegate operating at 60% after TB plate closes and boost goes slightly above desired... I’m stumped, and that doesn’t happen often... dealer has it... hopefully news to come
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #18 ·
They don’t know... they’ve had it a couple days and opening hotline ticket... it would be my truck...
 
1 - 18 of 18 Posts
Top