350R - rpm sputtering / floating

[AgSurfer]

Was driving my 350R yesterday afternoon and experienced some RPM sputtering / floating in 4th and also 5th gear between say 2.5 - 3.0k RPMs. Was applying gentle pressure to the throttle and essentially maintaining cruising speed. I could feel the car chugging a bit when this happened, as the throttle response was far from clean.

It was also an extremely windy day in NE Ohio yesterday - wasn't sure if all that wind could have been messing up the intake, MAF sensor, etc.

I've also read this issue can be caused by inoperative cruise control system (for which there is a Ford TSB), vacuum leak, and some other potential causes.

Curious if anyone else has experienced this issue before.

Appreciate any input.

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[DaveB]

Was driving my 350R yesterday afternoon and experienced some RPM sputtering / floating in 4th and also 5th gear between say 2.5 - 3.0k RPMs. Was applying gentle pressure to the throttle and essentially maintaining cruising speed. I could feel the car chugging a bit when this happened, as the throttle response was far from clean.

It was also an extremely windy day in NE Ohio yesterday - wasn't sure if all that wind could have been messing up the intake, MAF sensor, etc.

I've also read this issue can be caused by inoperative cruise control system (for which there is a Ford TSB), vacuum leak, and some other potential causes.

Curious if anyone else has experienced this issue before.

Appreciate any input.

I’m currently dealing with the same issue… I believe. I’ve got an 18 non-r. I tested my cruise, because I’ve never used it, and it is inop. The rpms hang up for a second, seems like forever, when I let off the clutch. It’s my daily driver so I haven’t really taken the time to check it out too much or take it to the dealer…. I am a mech at a hot rod shop and own my own performance and detail company, plus I don’t know that I trust the dealership?! I put my scanner on to see if there were any codes that possibly kicked without kicking the light, but there were none.
Reading the tsb that I saw, the fix is something about the tailshaft housing nuts on the trans backing off.? I wonder if there is a sensor or something there. I need to take the time to look

 

[AgSurfer]

Thanks Dave - this sounds very similar to my issue. I am also not throwing any codes. I rarely use cruise control, but did a couple times in the late fall and it was acting up... some times not even engaging. After a shut off and restart a few days later, cruise seemed to work ok but I did experience that odd rpm fluttering again.

Cars are in for their winter hibernation now, so I will be revisiting this in spring 2025.

 

[T7TheLama]

Vehicle Speed Sensor maybe? (OSS Sensor)

 

[wingnutt]

Check that your air filter is snugly attached…mine was loose and had many of the same signs not long ago

 

[WildHorse]

It's done for, so the only logical thing is to sell it to me.

 

[TonyNJ]

Maybe this....

https://www.mustang6g.com/forums/threads/tsb-19-2135-surge-or-hesitation.126435/

 

[DaveB]

Thanks Dave - this sounds very similar to my issue. I am also not throwing any codes. I rarely use cruise control, but did a couple times in the late fall and it was acting up... some times not even engaging. After a shut off and restart a few days later, cruise seemed to work ok but I did experience that odd rpm fluttering again.

Cars are in for their winter hibernation now, so I will be revisiting this in spring 2025.

I’ll let you know what I find, when I get my self to check!!!

Maybe this....

https://www.mustang6g.com/forums/threads/tsb-19-2135-surge-or-hesitation.126435/

that’s the one I’m talking about! Thank you. If it’s loose I don’t know if it just needs tightened or if anything needs held while tightening

 

[TonyNJ]

I’ll let you know what I find, when I get my self to check!!!

that’s the one I’m talking about! Thank you. If it’s loose I don’t know if it just needs tightened or if anything needs held while tightening

I feel something happening with my 350R around 3k rpm until about 4k but I'm not sure if that's just the magic kicking in.

 

[DaveB]

I feel something happening with my 350R around 3k rpm until about 4k but I'm not sure if that's just the magic kicking in.

Almost like a pulsation/ hesitation/surge? Almost like it’s struggling to get fuel for lack of better words?

 

[TonyNJ]

Almost like a pulsation/ hesitation/surge? Almost like it’s struggling to get fuel for lack of better words?

It's a surge, not so much a pulsation. Almost like it's slipping then kicks in. Not sure if it's the voodoo power band kicking in or trans slipping or this output shaft issue. I need to get under the car and check it out.

 

[526 HRSE]

I’m currently dealing with the same issue… I believe. I’ve got an 18 non-r. I tested my cruise, because I’ve never used it, and it is inop. The rpms hang up for a second, seems like forever, when I let off the clutch. It’s my daily driver so I haven’t really taken the time to check it out too much or take it to the dealer…. I am a mech at a hot rod shop and own my own performance and detail company, plus I don’t know that I trust the dealership?! I put my scanner on to see if there were any codes that possibly kicked without kicking the light, but there were none.
Reading the tsb that I saw, the fix is something about the tailshaft housing nuts on the trans backing off.? I wonder if there is a sensor or something there. I need to take the time to look

Tone ring. Happened to the best of us.

 

[526 HRSE]

It's done for, so the only logical thing is to sell it to me.

Yes, the motor is about to blow. The depostitioning sensor fluid is out of balance causing the shortshiftaplex to misplace itself at high idle under 200 rpms. Very dangerous. Should get rid of the car immediately.

 

[526 HRSE]

Maybe this....

https://www.mustang6g.com/forums/threads/tsb-19-2135-surge-or-hesitation.126435/

100%

 

[Talliuz]

Following this thread. I have had this issue on my 19 non R for the longest. The only reason I have not checked the tone ring is because it only happens after pulls. Very very rarely happens during normal driving

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