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  • 2015 - 2023 (S550) Mustang -General/Talk

2021 EcoBoost

  • Thread starter Thread starter EcoBeast2021
  • Start date Start date Oct 23, 2023
E

EcoBeast2021

Member
Oct 23, 2023
2
1
13
st. louis
Oct 23, 2023
#1
  • Oct 23, 2023
  • #1
So I purchased a 2021 EcoBoost Premium (10spAuto) from a very reputable dealer in my area. The test drive was fine, but as soon as I got it off the lot it began to stutter and I noticed that the shifts were very slow. At the first stop light off of the interstate a neck punishing down shift. I knew obviously something was wrong and called the salesman. It took them 3.5 weeks to get me in for service and then, when I got it in they said there was no transmission fluid in it.

They replaced the missing fluid and same story, car still doesn't shift right down shifts hard, and now it's stuttering like trying to die at lights and in park....

I took the car to O'Riley's to out it on a code reader to see what the problem was and it's not throwing a single code. How can the car be almost dying and not shifting right but also not coding ?

Is it possible to disable the monitoring ?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Box behind Walmart
Oct 24, 2023
#2
  • Oct 24, 2023
  • #2
Return it to the very reputable dealer and pick it back up once it's fixed.
 
Reactions: nickyb

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
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nevada
Oct 24, 2023
#3
  • Oct 24, 2023
  • #3
A very reputable dealer would have checked the fluids before letting the car off the lot.
All dealers are stealers, remember that and always be guarded when dealing with them.
I would return the car and demand my full refund.
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
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Middle of Maine
Oct 24, 2023
#4
  • Oct 24, 2023
  • #4
The CEL is primarily a emissions component failure light.
If the fault does not effect emissions, then likely there will be no code, or CEL.
Your vehicle may have codes stored that a generic code reader at the parts store does not read.
I had a 2024 Equinox in for a sun roof failure today. No CEL, but there was a code from the BCM for a short to ground on the lighting circuit, that shares info from the sun roof. Since it was not emissions related, there was no CEL.
You need to go back to the Ford Dealership, and if y9ou don;t trust that one, try another. They are not all the same.
All Transmission related codes will start with P0700 and go up in number P0701, P0702 ect, ect.
 
E

EcoBeast2021

Member
Oct 23, 2023
2
1
13
st. louis
Oct 24, 2023
#5
  • Oct 24, 2023
  • #5
I took it back to them today because on my way home from work it started smoking and not a little. Enough that I was flagged down and told to pull over because the guy thought I was on fire. Huge trail of thick white smoke behind me. Pulled over smoke engulfed my car, transmission leaking like crazy. They took the car and gave me a loaner guess we will see what they do about it.
 
Reactions: Noobz347
J

JonhDe31

New Member
Aug 23, 2025
1
0
1
London
Aug 23, 2025
#6
  • Aug 23, 2025
  • #6
EcoBeast2021 said:
So I purchased a 2021 EcoBoost Premium (10spAuto) from a very reputable dealer in my area. The test drive was fine, but as soon as I got it off the lot it began to stutter and I noticed that the shifts were very slow. At the first stop light off of the interstate a neck punishing down shift. I knew obviously something was wrong and called the salesman. It took them 3.5 weeks to get me in for service and then, when I got it in they said there was no transmission fluid in it.

They replaced the missing fluid and same story, car still doesn't shift right down shifts hard, and now it's stuttering like trying to die at lights and in park....

I took the car to O'Riley's to out it on a code reader to see what the problem was and it's not throwing a single code. How can the car be almost dying and not shifting right but also not coding ?
dubai super car hire
Is it possible to disable the monitoring ?
Click to expand...
Tough, I sympathize. Without transmission fluid — this is already an alarm bell, that there could be some other omissions when preparing the car for sale.

If after topping up ATF the behavior has not changed and there are still jerks/muffled at traffic lights — it is quite possible that there is a problem with the solenoids or the gearbox control module
Click to expand...
 
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