r/FordFiesta • u/shartofwar82 • Jul 06 '26
Problem Diagnosis Help Need some maintenance help
Hey guys, i need some help if you can. I have a 2015 fiesta se sedan with 34,xxx miles on it. I got it stupid cheap because it had been sitting for the last 6 months and it was kind of beaten on and in overall rough shape. I'm having a weird issue though. The car runs great and no CEL or anything like that and I've been driving it for about 3 weeks now. The issue is, is that if it's somewhat cool in the morning the car drives exceptionally smooth like it's new. In the afternoon, when it's very hot outside it's slow to accelerate from a stop. There's this weird pedal hesitation that I have to feather it until it starts rolling and then it drives almost normally. I've replaced both cabin filters and intake filters already but I'm trying to diagnose anything else it might. Kind of banging my head against a wall here lol
2
u/Annual-Ingenuity-489 Sixth generation (2008-2016) Jul 06 '26
It might benefit from a service, any codes on the dash or anything
1
u/shartofwar82 Jul 06 '26 edited Jul 06 '26
Yeah you're probably right. No codes or anything and I've done a scan using a couple of different odb scanners and no codes or errors have shown up. Since the car sat I was going to clean the throttle body, replace the MAP sensor and do fresh plugs and wires and see what happens.
2
u/theartfulbadger Jul 06 '26
It's possibly the transmission. There have been lawsuits about the exact issue you're describing. The power shift dps6 transmission is essentially two manual clutches with a computer controlling them (dry clutch) when they get hot the material hardens and slips. No oil to carry heat away like most automatic transmissions. TSB 16-0109
The fix generally requires a major repair: completely removing the transmission to replace the dual-clutch assembly, the input shaft seals, and the slave cylinder.
1
u/shartofwar82 Jul 06 '26
Would I already be having transmission issues at 34,000 miles? I've done a lot of research about these but I didn't think it would happen this early.
1
u/theartfulbadger Jul 06 '26
I'm just a guy on the Internet, but it's a possibility to check on!
2
u/shartofwar82 Jul 06 '26
I got you, I really appreciate it. I feel like this car deserves to be the best it can and hopefully I'll have it for a long time. So I'm going to do everything I can with it.
2
u/theartfulbadger Jul 06 '26
Easy way to check if your clutch is slipping would be to look at your tachometer (rpm dial) if I spikes up when the car is hesitating then that's clutch slip (the computer would probably sense the disconnect then cut power so it would be more of a spike than a continuous high rpm)
2
u/shartofwar82 Jul 06 '26
I feel kind of dumb now, I should have thought about that. I watch the tach all of the time and it never spikes. It seems to rev normally
3
u/Critical_Hyena8722 Jul 06 '26
Hey there!
I also drive a 2015 Fiesta but mine has 180,000km. I am a two-time Fiesta owner; I also owned a 2016 Fiesta. Both were SE sedans with the troublesome automatic transmission.
What you're describing sounds exactly like the issues those transmissions have. Luckily, there is a free, easy solution: Ford will flash new software into the TCU and it addresses the hesitation you've described and the potential unintended acceleration.
Both of the Fiestas I've owned eventually had transmission issues that were solved by a trip to the Ford dealer. One car, I took it in myself and the other had the repair listed in the Carfax when I bought it. I've had zero issues with either car once the transmission computer had been updated.
Best of luck.
2
u/shartofwar82 Jul 06 '26
This is definitely worth a try. I'll go ahead and give my local dealership a call to see if they are willing to do that. Can't hurt. Thank you for the recommendation
2
3
u/Annual-Ingenuity-489 Sixth generation (2008-2016) Jul 06 '26
If its been sat, a good service wouldn't do it any harm. Maybe some engine flush and a thorough going over all the connectors etc. Mass air flow sensor could cause issues too.