Throttle stuttering on acceleration

[Morn]

This is a hesitation/stutter. I push on the gas and it goes then doesn't, then goes, then doesn't. Feels kind of like how bad gas or low tranny fluid level feels.

I posted this elsewhere, but it sounds like the same issue I'm having. It's not really noticeable in 2H, but in 4A I definitely feel it, and if you put it in Sport mode and switch to 4A, you really feel it. And this is a very quick misfire type of stutter.

The sweet spot to always get it to happen is around 40MPH with light to moderate accel. Doesn't happen (or not detectable) when gunning it.

I've taken it to the dealer about this. They said they've seen this before and replaced all the plugs to fix it. When checking it after the work was done, they said they detected a little bit of that behavior, but that it's normal to see that in 4A and called it good. At first I thought it was resolved, but the more I drove it (and then discovered how bad it was in Sport+4A), I realized it hadn't really gone away.

So, I'm going to take it back to the dealer when I can.

Change the plugs to Motorcraft SP542 @ .025"

Are those plugs/gaps different than OEM? Wondering which ones my dealer used when they swapped them out.

 

[kpg81]

I posted this elsewhere, but it sounds like the same issue I'm having. It's not really noticeable in 2H, but in 4A I definitely feel it, and if you put it in Sport mode and switch to 4A, you really feel it. And this is a very quick misfire type of stutter.

The sweet spot to always get it to happen is around 40MPH with light to moderate accel. Doesn't happen (or not detectable) when gunning it.

I've taken it to the dealer about this. They said they've seen this before and replaced all the plugs to fix it. When checking it after the work was done, they said they detected a little bit of that behavior, but that it's normal to see that in 4A and called it good. At first I thought it was resolved, but the more I drove it (and then discovered how bad it was in Sport+4A), I realized it hadn't really gone away.

So, I'm going to take it back to the dealer when I can.

Are those plugs/gaps different than OEM? Wondering which ones my dealer used when they swapped them out.

They probably put the factory SP552's in there and gapped them wrong

I'd just do it yourself. Many people on this forum and other ecoboost forums have had a lot of luck putting in the Sp542's and that made their truck run better

I am convinced Ford used those plugs at that gap for fuel/EPA reasons. They knew what they were doing IMO. Probably for MPGs and not a better running truck. Just like how they skimped on the crappy rear suspension setup using regular leaf springs and a 2" block. Lame

 

[Morn]

They probably put the factory SP552's in there and gapped them wrong

Did some checking. According to the manual, the factory plug is SP-534. Is that what you meant? Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA

And the default gap is .030-.033. Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA

I'd just do it yourself. Many people on this forum and other ecoboost forums have had a lot of luck putting in the Sp542's and that made their truck run better

Sounds good. My problem is I have way less time to wrench than I used to, but I'll try to carve out some time and give it a shot. Also, I'm due for my first service soon (I'm at 8900 miles), so I may use that time to talk to the dealer about this again just to give them an opportunity to take a look. I'm guessing they'd wave off any suggestion to use a different plug/gap other than factory, but it can't hurt to mention it.

 

[kpg81]

Did some checking. According to the manual, the factory plug is SP-534. Is that what you meant? Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA

And the default gap is .030-.033. Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA



Sounds good. My problem is I have way less time to wrench than I used to, but I'll try to carve out some time and give it a shot. Also, I'm due for my first service soon (I'm at 8900 miles), so I may use that time to talk to the dealer about this again just to give them an opportunity to take a look. I'm guessing they'd wave off any suggestion to use a different plug/gap other than factory, but it can't hurt to mention it.

I had 552's in my 18 when i pulled them out

 

[Sharkus29]

Did some checking. According to the manual, the factory plug is SP-534. Is that what you meant? Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA

And the default gap is .030-.033. Source: http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA



Sounds good. My problem is I have way less time to wrench than I used to, but I'll try to carve out some time and give it a shot. Also, I'm due for my first service soon (I'm at 8900 miles), so I may use that time to talk to the dealer about this again just to give them an opportunity to take a look. I'm guessing they'd wave off any suggestion to use a different plug/gap other than factory, but it can't hurt to mention it.

I changed my spark plugs to the SP542's and they were already gapped at .025. The truck runs amazing, I highly recommend trying them

 

[ss_raptor]

I’ve had this issue from day one. I’ve had a Ford Master tech look at the truck all day hooked up to the computer while they test drove the truck and he said it was normal. It’s not normal and since not all the truck are doing it I don’t think it’s normal. I’m just surprised Ford hasn’t figured out the root cause of the issue. I’ve changed the spark plugs from stock to the NKG 6509 gapped at .025 with no success. I’m down to try anything so I’m going to give the SP542 gapped at .025 a try next. I did notice the different colors of the stock plugs when I took them out.. I don’t know how to read plugs, but I do know they all should be the same color. Maybe this has something to do with the root cause of this bucking and snorting some seem to be experiencing. I have this as evidence when I take it to the dealer once again. I’m interested to see how the NKG look when I put in the SP542. Also, I ran MPT’s tune until they told me to pull it off on my 2018. I will say MPT’s tune didn’t fix the issue completely, but it was a lot less noticeable. Now while I wait till MPT figures out the 2018 issues I’m running gearheads tune. Problem is back and it feels worse than stock. This kind of tells me it might be something with the transmission tune. And as you can see It definitely doesn’t seem to be affecting performance for 0-60 runs on gearheads tune.

 

[vr4henry]

I’ve had this issue from day one.

I've had this stutter happen 1 time with ~2000 miles on truck. (now ~7800 and haven't seen again).

I replaced plugs at 7500 miles and they looked like this. (looks good to me? maybe a smidge rich) All gapped at 30 from factory.

 

[03'Darin]

I’ve had this issue from day one. I’ve had a Ford Master tech look at the truck all day hooked up to the computer while they test drove the truck and he said it was normal. It’s not normal and since not all the truck are doing it I don’t think it’s normal. I’m just surprised Ford hasn’t figured out the root cause of the issue. I’ve changed the spark plugs from stock to the NKG 6509 gapped at .025 with no success. I’m down to try anything so I’m going to give the SP542 gapped at .025 a try next. I did notice the different colors of the stock plugs when I took them out.. I don’t know how to read plugs, but I do know they all should be the same color. Maybe this has something to do with the root cause of this bucking and snorting some seem to be experiencing. I have this as evidence when I take it to the dealer once again. I’m interested to see how the NKG look when I put in the SP542. Also, I ran MPT’s tune until they told me to pull it off on my 2018. I will say MPT’s tune didn’t fix the issue completely, but it was a lot less noticeable. Now while I wait till MPT figures out the 2018 issues I’m running gearheads tune. Problem is back and it feels worse than stock. This kind of tells me it might be something with the transmission tune. And as you can see It definitely doesn’t seem to be affecting performance for 0-60 runs on gearheads tune.

Is the issue you are having most noticeable under moderate acceleration, at steady throttle and more noticeable if you are climbing a hill under those conditions? That's what my truck does and has done ever since new. I have over 21,000 miles on the truck now. My truck also does it under lower loads but it's not that noticeable. Feel just like an engine miss to me.

I've waited expecting Ford to come out with an update that would take care of the issue. However last week I finally took time and had our lead tech go out with me and data log a bunch of stuff trying to figure out what the issue was. I've talked with him several times since the truck was new and I noticed the problem. He had been watching for TSB's, updates or service tech message board threads regarding the problem but never saw anything.

Our lead tech thought for sure it was tranny related and I was positive it was an engine miss.

First thing we did was data logged a bunch of the tranny outputs that are available. All of that was good.

Then we looked for cylinder misfires and nothing.

I could duplicate the issue on every pull like I described above. So we were out for probably 45 minutes checking multiple different things. We finally tracked the issue down to the throttle body actually making very quick adjustments even though the throttle pedal showed I was holding the pedal steady. The PCM was actually commanding the throttle body to do that. Our lead tech is stumped. He couldn't find anything that was sending data to the PCM that would have been causing it to demand the throttle body to make those abrupt changes.

He sent several data logged runs with a detailed description to the Ford tech hotline. Ford engineers will review them and get back to us with most likely some other ****** we'll need to run.

We'll probably hear back today or tomorrow on this. I'll update our findings when I have any more info.

 

[ss_raptor]

Is the issue you are having most noticeable under moderate acceleration, at steady throttle and more noticeable if you are climbing a hill under those conditions? That's what my truck does and has done ever since new. I have over 21,000 miles on the truck now. My truck also does it under lower loads but it's not that noticeable. Feel just like an engine miss to me.

I've waited expecting Ford to come out with an update that would take care of the issue. However last week I finally took time and had our lead tech go out with me and data log a bunch of stuff trying to figure out what the issue was. I've talked with him several times since the truck was new and I noticed the problem. He had been watching for TSB's, updates or service tech message board threads regarding the problem but never saw anything.

Our lead tech thought for sure it was tranny related and I was positive it was an engine miss.

First thing we did was data logged a bunch of the tranny outputs that are available. All of that was good.

Then we looked for cylinder misfires and nothing.

I could duplicate the issue on every pull like I described above. So we were out for probably 45 minutes checking multiple different things. We finally tracked the issue down to the throttle body actually making very quick adjustments even though the throttle pedal showed I was holding the pedal steady. The PCM was actually commanding the throttle body to do that. Our lead tech is stumped. He couldn't find anything that was sending data to the PCM that would have been causing it to demand the throttle body to make those abrupt changes.

He sent several data logged runs with a detailed description to the Ford tech hotline. Ford engineers will review them and get back to us with most likely some other ****** we'll need to run.

We'll probably hear back today or tomorrow on this. I'll update our findings when I have any more info.

Yes, when climbing a hill it's most noticeable. Also, I feel it in sport mode but its a lot less noticeable. Again if you look at my plugs you will see 3 of them are a lighter color then the other 3. I made the mistake of not noting where the plugs came out of. When I take out the NKG plugs I'll make sure to note the location of the plugs. Shouldn't my plugs all be the same color? Have you checked your plugs?

 

[03'Darin]

Yes, when climbing a hill it's most noticeable. Also, I feel it in sport mode but its a lot less noticeable. Again if you look at my plugs you will see 3 of them are a lighter color then the other 3. I made the mistake of not noting where the plugs came out of. When I take out the NKG plugs I'll make sure to note the location of the plugs. Shouldn't my plugs all be the same color? Have you checked your plugs?

I haven't checked my truck for the symptoms in any other mode than normal so I don't know if it is better or worse.

I was going to just pull plugs and change them after reading all of the threads here. But instead I decided to have the shop data log it first to see if it was actually missing, which it wasn't. So it's not a spark plug issue.

Yes, plugs should all be close to the same color