Intermittent misfire 2019 Ford F-150 2.7 Ecoboost S-Crew 4x4

[1911CHAMPION]

Good afternoon!

Looking for some suggestions or advice on how to proceed/diagnose an intermittent misfire that I am having with my truck. (migrating from #1, to #3 & #6)

It is a 2019 Ford F-150 with the 2.7 Ecoboost engine, 4x4 SuperCrew and is completely stock.

It currently has about 89,500 miles on the odometer, and I replaced the spark plugs with new Motorcraft SP594's all gapped to 0.030" in Sept of 2023 when the truck had 76,400 miles on it. I bought the truck used in Nov of '22 with about 65,000 miles on it; it was a lease return. Have towed a 32' camper with it about half a dozen times over the last 2 summers and it has operated and ran flawlessly. Yes, it has the 10R80, and no I haven't had a single transmission issue with it. I clear the adaptive learning tables once a year (about every 10,000-12,000 miles) and do the proper relearn procedure and it shifts absolutely like butter. I ordered 18 quarts of MC ULV from RA so that I can do a 3X drain and fill on the transmission some time here in the next few weeks before the Memorial Day weekend.

I had to take a trip to Cleveland from SW Michigan back in mid-March and on my way back as I was leaving a rest area I was getting on it kind of hard and felt it stuttering a little. I was like "that's odd, it's never done that before." I shifted to manual mode on the highway (without other traffic around) and accelerated at WOT in 6th, 7th, and 8th gears separately and it did the stutter in each gear from 60-75 until I let off. There is no stuttering at cruising speed, it's absolutely smooth. At that time it hadn't yet produced a CEL. It doesn't stutter/misfire until the engine load increases and turbos spool up past about 3500 rpm at WOT.

Thinking it was a fuel related issue I drove the truck normally till it was almost empty and then filled it up with premium, and added the appropriate amount of Lucas fuel injector cleaner for the 26 gallon tank. No change, still stutters under the previously mentioned conditions, and even went down as far as 5th gear in manual mode and hit it WOT and it does it there too. Seems to be a DI fuel related issue? From my understanding the Port fuel injection is operating primarily at idle and low engine load and low boost levels and the DI fuel injection kicks in at higher engine load and higher boost pressure.
I have used primarily CostCo regular octane in the truck, except for when I am on the road.

I finally got it to produce a P0301 code about 2 weeks ago. I hooked up my OBD reader and cleared the CEL and drove it normally again till this past weekend. I ragged on it again for one pull on the highway and now it's showing a P0303 and P0306 misfire. So it's not confined to one cylinder, and I did pull the spark plug out of #1 last week and looked at it and it looks great. The insulator isn't cracked and the gap was still measuring 0.030".

I've read some things in various forums about condensation accumulating in the intercooler and it causing a misfire on #6, and that could be a possibility because unless I have to take a road trip I drive 9 miles each way to/from work and my speed never goes above 50 mph. I haven't drilled a 1/16" weep hole in the bottom of the intercooler. Thinking I will climb under the truck and do that this coming weekend, and see if any crud comes out...

I topped off the gas tank on Saturday and added one of the 21 oz cans of Berryman B-12 Chemtool Fuel Injector Cleaner, thinking it needed something more potent if it's a clogged injector.

I have been changing the oil every 5-6,000 miles using either Kirkland Signature FS, or Quaker State FS and a WIX or Motorcraft filter. Not that that would matter for this problem.

Any suggestions would be greatly appreciated! Thanks!

Also, I have Forscan installed on my laptop and the requisite OBDLink EX USB to OBD cable that they recommended to use with Forscan.

 

[tcp71]

I drilled the weep hole on my 2016 the day it came home from the dealer. It amount of crud spewed out around that hole, on my garage floor under the hole and even on the wall in front of the hole is quite impressive. Can't hurt to try that.

 

[FowVay]

Did you get any additional information with the DTC P code? Normally Ford will identify what triggered the code by adding additional info with the P code. Example: P0306:00-EC (triggered at the cylinder) or P0316:00-68 (triggered when the misfire occurs during startup).

 

[1911CHAMPION]

I need to hook up FORScan to it and check. I haven’t actually done that yet.

 

[SubieRubyRoo]

Catch can? I’d check the plugs again to be safe; I changed mine at ~77k and they could have easily made it to 100k. Actually, the first factory part that actually needed to be replaced just happened on my truck last Saturday; the driver rear brake pad was finally down to metal-on-metal at 97,258 miles.

I’m definitely not saying every truck will make it this far, but after changing diff fluid at ~72k, trans @ ~75k, plugs at ~77k… all of mine were perfectly serviceable and would have gone longer. I don’t change things just because “it’s time” I change things when something has changed for the negative. I think messing with some things brings additional heartache because if it ain’t broke, don’t F(ix) with it!

Best of luck figuring out your misfire. I suggest a CFM Titan II intercooler with a Turbosmart Vee-Port BOV. Wait for a holiday sale; I got my intercooler and BOV for about $50 more than regular price on the intercooler with a BF/CM sale.

 

[meep]

My 2018 2.7 started losing coil packs around 88k miles. Key symptom is that it bucks more under load, especially if it’s under load and lower rpms, like manually shifted. Ford oem runs somewhere from $86 to $120 per coil pack. I replaced one, and then another showed 2 weeks later.

 

[1911CHAMPION]

But to have 3 coil packs all go at basically the same time?

Now the cylinder one misfire is gone and it is now affecting 3, 4, & 6

High pressure fuel pump?

 

[SubieRubyRoo]

But to have 3 coil packs all go at basically the same time?

Now the cylinder one misfire is gone and it is now affecting 3, 4, & 6

High pressure fuel pump?

View attachment 275061

It’s always possible, especially since 1. You’re just over the mileage @meep stated his failed, and 2. 2 weeks later another one went. Sounds like you’ve been chasing this for at least that long?

Best bet, replace all 6, and only buy Ford coil packs, or maybe the MSD coils for your 2.7, go with those.

https://www.drivingline.com/article...ormance-coil-packs-for-ford-ecoboost-engines/

 

[1911CHAMPION]

I have no intention of tuning the truck, so do I gain anything by putting the MSD coil packs in it?

IF I ever did put a tune in it, it would be an E85 tune since that is readily available in this area. And from I read online, the fuel system in the 2018+ 2.7 Ecoboost F-150s can handle it without changing a thing (aside from putting a tune in the truck for it obviously).

 

[meep]

Ugh. I would hate for it to be the hpfp. I think … suspect that it would not be the pump as it serves all of the cylinders. If it were on the fuel side, a bad rash of injectors, errr… watch the plumbing … 3, 4, and 6, are they collocated on the fuel flow? Injector breakdown, or maybe some shrapnel in the system? I would not want the catastrophe of losing an injector and flooding a cylinder. It might be worth changing the oil just in case there’s excess fuel in play which could contribute to dilution. Might pull and inspect the plugs for clues on mixture and cylinder health, maybe use a bore scope to see if any piston tops look wet?

That said, re-reading the OP, the WOT runs in the upper gears all scream coil/plug issues.

 

[1911CHAMPION]

I recorded a fuel rail pressure log yesterday driving home from work using the OBD Fusion app. Seems to jump all over the place, unless this is normal? I stayed out of the throttle and drove no more than 30% or above 3,000 rpm’s the entire way home.

I’m not even sure what the correct fuel rail pressure should be at idle vs at operating/cruising speed.

 

[YZJB]

I recorded a fuel rail pressure log yesterday driving home from work using the OBD Fusion app. Seems to jump all over the place, unless this is normal? I stayed out of the throttle and drove no more than 30% or above 3,000 rpm’s the entire way home.

I’m not even sure what the correct fuel rail pressure should be at idle vs at operating/cruising speed.

Which rail? This engine has low pressure and high pressure fuel systems, and switches between (and blends) them depending on engine speed and load.

This is highly likely to be an ignition issue (coils or plugs) and unlikely to be a fuel issue, based on your explanation of its behaviour.

 

[meep]

Those numbers indicate HP fuel rail … low pressure rail would be typical PFI numbers.

if your engine spent up to 30% of its time over 3k, I think it was moving in and out of the DI use territory. The PFI is dominant under low load and high load conditions, with DI phasing in some ambiguous realm maybe around 30% load, reaching its max cap, and then PFI phasing back in for the highest output. It would not surprise me if it modulates pressure to avoid unnecessary loss/wear.

 

[SubieRubyRoo]

Those numbers indicate HP fuel rail … low pressure rail would be typical PFI numbers.

if your engine spent up to 30% of its time over 3k, I think it was moving in and out of the DI use territory. The PFI is dominant under low load and high load conditions, with DI phasing in some ambiguous realm maybe around 30% load, reaching its max cap, and then PFI phasing back in for the highest output. It would not surprise me if it modulates pressure to avoid unnecessary loss/wear.

2.7 may be different, and it’s counter to what I would have thought, but I’m pretty sure from what I read was that at low loads the PFI is essentially off, due to increased emissions; this is where the DI “shines” if you will. Then, at mid-high levels due to lots of airflow and mixing, the PFI picks up.

I haven’t measured or recorded my rail pressures, ever, but yes those graphs look like there’s an issue on the HPFP. Yes, almost everything besides tuner says the 2.7 has enough HPFP and LPFP capacity to run 100% E85; on the 3.5 some tuners say it’s limited to 30% and others 50% E85 unless the LPFP, HPFP, or both are upgraded to high flow units, and the tune they provide is fueled differently depending on which pump has been upgraded.

If I were to replace or upgrade my HPFP, I’d probably go with xDI pumps. The In tank would likely be a 440lph Deatschwerks with a boost-a-pump just to be safe. I can’t imagine the power of a 3.5 with a 100% E85 race fuel tune. 5 Star Tuning considers the 10R80 capable of 800ft-lbs in stock tune, and that would likely be pushing it oh-so-close.

 

[NibbanaBanana]

Sounds like ignition. If you pulled the plugs and they look fine, I would change a coil and see if it makes a difference.

 

[meep]

2.7 may be different, and it’s counter to what I would have thought, but I’m pretty sure from what I read was that at low loads the PFI is essentially off, due to increased emissions; this is where the DI “shines” if you will. Then, at mid-high levels due to lots of airflow and mixing, the PFI picks up.

I haven’t measured or recorded my rail pressures, ever, but yes those graphs look like there’s an issue on the HPFP. Yes, almost everything besides tuner says the 2.7 has enough HPFP and LPFP capacity to run 100% E85; on the 3.5 some tuners say it’s limited to 30% and others 50% E85 unless the LPFP, HPFP, or both are upgraded to high flow units, and the tune they provide is fueled differently depending on which pump has been upgraded.

If I were to replace or upgrade my HPFP, I’d probably go with xDI pumps. The In tank would likely be a 440lph Deatschwerks with a boost-a-pump just to be safe. I can’t imagine the power of a 3.5 with a 100% E85 race fuel tune. 5 Star Tuning considers the 10R80 capable of 800ft-lbs in stock tune, and that would likely be pushing it oh-so-close.

I thought the same as you @SubieRubyRoo - however there is a white paper floating around, including on bitog, that mapped it all out. Direct injection is used where it is most efficient, which is under moderate loads. Now a bunch of videos pop up first instead of a rather formidable white paper that was coming up first a couple of years ago. Low loads and peak loads use the PFI. The transitions of overlap for the two systems is very broad - they are both active together in different ratios more than I thought they would be.

 

[YZJB]

I thought the same as you @SubieRubyRoo - however there is a white paper floating around, including on bitog, that mapped it all out. Direct injection is used where it is most efficient, which is under moderate loads. Now a bunch of videos pop up first instead of a rather formidable white paper that was coming up first a couple of years ago. Low loads and peak loads use the PFI. The transitions of overlap for the two systems is very broad - they are both active together in different ratios more than I thought they would be.

“Peter Dowding, Ford’s chief engineer of powertrain gasoline systems, revealed a different strategy. Ford uses PI alone at idle and at low rpm for smooth, quiet, and efficient engine operation. As rpm and load increase, fuel delivery becomes a programmed blend of PI and DI. In contrast to Toyota’s methodology, Ford’s PI is always operating, responsible for at least 5 to 10 percent of the fuel delivery.”

Source: https://www.caranddriver.com/news/a...-engines-have-both-port-and-direct-injection/

 

[meep]

“Peter Dowding, Ford’s chief engineer of powertrain gasoline systems, revealed a different strategy. Ford uses PI alone at idle and at low rpm for smooth, quiet, and efficient engine operation. As rpm and load increase, fuel delivery becomes a programmed blend of PI and DI. In contrast to Toyota’s methodology, Ford’s PI is always operating, responsible for at least 5 to 10 percent of the fuel delivery.”

Source: https://www.caranddriver.com/news/a...-engines-have-both-port-and-direct-injection/

Good article, yes

 

[thastinger]

Coil packs breaking down and producing a spark that is to weak to lite off under high cylinder pressures

 

[irekm]

I had exact same issues 3.5ecoboost, changed the gapped plugs still misfire under load, called ford to order all new coils and when they told me a price for them I was Ok, that is expensive I will just scan to see which one is the faulty one.
And then parts guy says to me, did you ever change the boot on the coils because those are serviceable items, I said no i didn't but I will.

Got the boots, in Canada $15 a piece, swapped them and freaking voila no missfires anymore. Total milage on the tunned truck 270k km form which about 260k km on different tunes . Still on the original coils .

When I looked on those rubber grommets with little spring inside I would never freaking guess that they would solve my problem