Throttle stuttering on acceleration

[smurfslayer]

Very few owners have this issue.

Even fewer owners have the stumble caused by condensation in the charge air cooler; as in .... zero.

Guess who’s back...

 

[sobiloff]

The lack of power at part-throttle happens on mine, and it's quite annoying. I'll register a complaint when I bring my truck in for the seatbelt recall, and I've bought a set of the cooler plugs that I'm willing to try, but I think the real fix needs to be done by Ford in the ECU.

 

[mezger]

So I made it a point to pay attention to mine this week.

Factors that have changed since my last post which could affect my observations:

- Extended period of cool weather.
- Another 1k miles on the clock.
-- Truck learning
-- Me learning
- I'm spending more time in auto mode instead of manual because the nannies more often deny my fun in manual mode.

WRT my comment on traction control, it doesn't seem to modulate it, I think that was placebo.

It seems my symptoms are reduced, but not gone. When I pay attention for them... I notice they're still present. Could be that I'm just getting used to it and have learned to anticipate + ignore them, could be that they're actually diminished as the computer does something with its maps (?? have no idea if and how it 'learns'). Could also be that they're less noticeable in auto mode or that my driving style has changed somewhat now that I'm more accustomed to the truck's behaviors.

I think it's a mix of the above because early on, I recall the stutter being pretty damn front and center, so I do think that for the past few weeks my truck's 'stuttering' is much less drastic than it had been during the first thousand miles.

WRT the low rate of reporting: I doubt this issue is uncommon, it's been present on all Gen 2s I've driven thus far. I speculate that a lot of drivers don't even notice it, either due to driving style (e.g. it takes a particular set of conditions to activate it. Maybe they're never in manual mode + sport, stuck in traffic all the time so not they're doing what I'm doing, babying the truck, not spending time cruising on the interstate, etc) or due to already being accustomed to this behavior from other turbo cars (again, one of my BMWs does something similar).

LOL @ the sasquach comments on this thread. I love my truck, but this thing is far from the epitome of driver's car engine and transmission tuning.

 

[smurfslayer]

So I made it a point to pay attention to mine this week.

<merciful snip>

WRT the low rate of reporting: I doubt this issue is uncommon, it's been present on all Gen 2s I've driven thus far. I speculate that a lot of drivers don't even notice it, either due to driving style (e.g. it takes a particular set of conditions to activate it. Maybe they're never in manual mode + sport, stuck in traffic all the time so not they're doing what I'm doing, babying the truck, not spending time cruising on the interstate, etc) or due to already being accustomed to this behavior from other turbo cars (again, one of my BMWs does something similar).

LOL @ the sasquach comments on this thread. I love my truck, but this thing is far from the epitome of driver's car engine and transmission tuning.

The ecoboost really is the best engine choice for the Raptor, especially the 2017.5 EB that I have.

I think the issue is that it’s not bucking and snorting in protest, it’s just making micro adjustments thinking it’s doing the right thing when really it’s not. Darin was saying he only gets the issue at steady state throttle, among other factors. I’m rarely at exactly steady throttle. and honestly, I love sport mode for traffic.

 

[mezger]

Yep, 'micro adjustments' are one way I'd describe it.

In my head, it feels like it's hunting for the bleeding edge of timing advance + lean, then backing off. Then repeat. I describe it as timing because it happens so quickly. But agreed, as I've become more accustomed to the truck's behavior, my driving style has changed and I believe that's one of the reasons I'm noticing it less. Also, I haven't gotten it on the interstate for a few weeks.

That said, it's still there if I pay attention to it.

I'd probably sport mode automatic 100% of the time if there was some third automatic mode where it'd behave like sport mode but 'relax' from a WOT session more rapidly. Sport mode is awesome for sustained hooning, but not so good when you want to point and shoot and then shut down when DDing.

 

[ArmyTanker]

I purchased my 18 Mag Grey Raptor about 2 months ago. I added a Roush CAI and peddle commander. I too had noticed a sluggish throttle tip in point, mid range throttle delay and some surging feeling under full throttle. After joining the site, just been looking around and this is my first post. This thread was of great interest due to it matching many of my concerns, so today I decided to try the SP 542 plugs, left them gapped as they came out of the box. After installation, went for a test drive to the grocery store for the Wife. On the way there, throttle felt way better but noticed I had some pinging at mid to full throttle. After stopping at the grocery, back on the road and the pinging is gone? Any guesses why on both??
The throttle seems better throughout, used to it would seem you have it throttle and it would take a millisecond and then it would cone in hard. Now, it seems to come in instantly and smoothly as you apply more pressure. But because it doesn’t come in delayed and hard as before, can’t yet tell if it makes the same power overall, but it is way smoother. The pinging happening and going away, does concern me, any wisdom from the group would be much appreciated. Many thanks

Well, the pinging/clatter is back under mid to heavy throttle after changing to the SP 542 plugs. It may be just one plug, sounds like it is on the drivers side. Any suggestions on how to tell which plug? I left the gap as it was coming out of the box on the SP 542s, so would not think it is that. I do like how the plugs seem to have improved initial throttle and seems to have smoothed our shifting, but this pinging/clatter is concerning. Looking for suggestions from folks a lot smarter than me on how to diagnose and remedy. Thanks

 

[03'Darin]

Well, the pinging/clatter is back under mid to heavy throttle after changing to the SP 542 plugs. It may be just one plug, sounds like it is on the drivers side. Any suggestions on how to tell which plug? I left the gap as it was coming out of the box on the SP 542s, so would not think it is that. I do like how the plugs seem to have improved initial throttle and seems to have smoothed our shifting, but this pinging/clatter is concerning. Looking for suggestions from folks a lot smarter than me on how to diagnose and remedy. Thanks

If you are getting pinging/clattering that is different than the issue we are discussing here.

First off are you sure it's pinging/clattering? There has been waste gate rattle issues that could possibly be confused with that. Also the cylinder firing/misfiring is monitored pretty closely by the PCM and should trigger an engine light.

I'd suggest if you are still under bumper to bumper warranty take it to the dealer. They can monitor the cylinders firing and determine exactly which one it is.

Some update on my issue we've been discussing:

Every 3.5 Ecoboost motor since 17' (that's when they bumper the tq on the base Eco from 420 to 470 and got the 10spd auto) has this condition. Even the base 3.5 Eco thats not in the Raptor. That motor just isn't nearly as noticeable. The reason the Raptor tune makes it worse is because they are squeezing more power out of the same motor so the condition is more pronounced.

Higher octane fuel does reduce the affects but it's defintely still there and noticeable.

Out of all of the Raptors we have sold there are only 2 of us that have complained about the issue. Me being one and the first.

Cold or even cooler weather makes it more noticeable.

I hate it but have learned to deal with it. My truck is creeping up on 34k miles pretty directly.

Oh yeah and the spark plug change makes ZERO difference with this.

 

[03'Darin]

Small update from my end. Did the 542 plugs yesterday and confirmation bias or not it “seemed” to run a bit smoother.

Double checking that the 542s are the same length as the stock plugs before putting them in:



All 6 of the old plugs looked normal to me...no real concerns from what I can discern:



Checked the sensors again since I was in the engine compartment and all were oil-free.

After a short test drive with the new plugs, I also ran a can of CRC valve/turbo cleaner through the motor via the throttle body...took longer than I thought, but had the kid who’s getting my old truck running the throttle, so he was happy to get some time on a Raptor throttle, even if it was just to hold it between 2,000-2,500 rpm!

After getting the intake back together, took it for a couple towns over to pick up some VP 100 octane, and not surprisingly it was running a little rough at low rpm/throttle until I got out of my neighborhood as residual cleaner made its way through the intake/exhaust. There was a particularly rough ‘stumble’ when I rolled on the throttle pulling away from the stop sign leaving the neighborhood, then a huge puff of white smoke out both tail pipes. Guess some carbon got blown out!

Ran smooth as silk after that...

Have a large bottle of Techron in the tank as well as some VP octane boost and cleaner along with another fill up of Shell VPower 93 octane.

Gonna run it down to 1/4 tank or so and add this next:



Then I’ll do the CRC valve deposit/turbo cleaner one more time.

After that will do my test circuit again to see if the part throttle intermittent stumble is any better or worse. Suspect it’ll be unchanged if it is indeed an engine map/ECU programming issue where the throttle body is feathering open and closed very quickly ... and which my untrained/unprofessional observation in an uncontrolled environment of the instant mpg bouncing up and down on a smooth road would point to as well.

At least I can rule out octane as the cause for the stumble if it does reoccur!

Edit: Has anyone running an aftermarket tune noticed the stumble? If this is indeed just some poor programing, I’d think a tune developed on a dyno would be able to smooth out the unnecessary throttle oscillations...then again, I’d think the factory developers/program managers, engineers, and programmmers would fix that too, even if they are running a compromised tune to account for crap fuel being put in the truck.

Sorry been busy and haven't been on here for a bit. Tune makes no difference. I don't know for sure but I think when they tune it they just change the commanded %'s using the existing factory tuning. So the flaw in the tuning is still there and isn't changed.

 

[91Eunos]

Well, the pinging/clatter is back under mid to heavy throttle after changing to the SP 542 plugs. It may be just one plug, sounds like it is on the drivers side. Any suggestions on how to tell which plug? I left the gap as it was coming out of the box on the SP 542s, so would not think it is that. I do like how the plugs seem to have improved initial throttle and seems to have smoothed our shifting, but this pinging/clatter is concerning. Looking for suggestions from folks a lot smarter than me on how to diagnose and remedy. Thanks

Sounds like it needs to go in for service.... could be a lot of things. Maybe something cheap and easy to fix like a loose fitting, or the beginning of a rod bearing going out.

 

[ArmyTanker]

Sounds like it needs to go in for service.... could be a lot of things. Maybe something cheap and easy to fix like a loose fitting, or the beginning of a rod bearing going out.

I have an appt in the morning