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

'15 Ecoboost Issues

  • Thread starter Thread starter dnbonds
  • Start date Start date Sep 22, 2016

dnbonds

Active Member
Dec 17, 2013
363
66
39
Hampton, VA
Sep 22, 2016
#1
  • Sep 22, 2016
  • #1
So today I've encountered some weird issues with my '15 ecoboost. Has about 20.5k miles on it, i got it in March with 7.5k miles used at a chevy dealership (yeah i know, but the deal i got was pretty good in my opinion). I put a decent amount of miles on it since getting it in March (13k miles). I use it as a daily and do a lot of 250 mile trips one way to visit family frequently. I plan on keeping this for a long time so im not worried about mileage, i dont believe in keeping a car low milage. If im paying for it im going to use it.

Well anyways, the issue I'm having is that when I start the car with the clutch in and the shifter in neutral the engine will bog down and stall. I've checked the oil which was changed about 3-5k miles ago with Mobil 1 Full Synthetic. It looked a little dark but still had color to it and the oil reset gauge has the life at 51%. Also, during moderate acceleration with maybe 5-10 psi of boost in first gear I heard a metal clanging sound with the engine RPMS dropping and bouncing. I said screw it and took it really slow back home after work and its parked now.

Only mods I have done to it are: JMS BoostMax (they claim its warranty friendly so i chose that over a tune), gibson catback, and a CAI. My driving habits are spirited but i never give it more than a little throttle under 2k rpms because I know the boost can damage the engine at low rpms. These issues suddenly popped up today with no fore warning.

I haven't seen a whole lot of issues posted on many websites about ecoboost issues so im documenting my experience here as this is going to be the first vehicle i'll have warranty work done to. I plan on calling JMS tomorrow morning and verify that the boostmax chip is warranty safe and that they'll stand by that statement in case Ford decides to void my warranty. After that im going to take my ecoboost into the dealership during my lunch break and see what they can do.

Any help or tips from experience would be very helpful. I'll check this thread tomorrow morning if you guys have anything.

Thank You and I hope I don't get screwed by Ford, I really love this car.
 

dnbonds

Active Member
Dec 17, 2013
363
66
39
Hampton, VA
Sep 28, 2016
#2
  • Sep 28, 2016
  • #2
Called JMS Friday morning and they said to remove the chip because that's what they're warranty friendly statement means. After removing the chip, the car drove without issue. Still took it into the dealership and they took it on two test drives and didn't find a single issue, also couldn't pull any codes from it. So within the 3 months of having a JMS BoostMAX, the chip itself went bad. The chip is on back-order so I'll have to wait a few weeks before JMS can send me a new chip. Its amazing how lacking the car feels now without any modifications. I took a 5.0 out on a test drive while they were waiting for a technician to free up for my ecoboost. The GT sounded really nice and the naturally aspirated engine has great instant power but I think the ecoboost isn't too far behind and definitely not worth paying extra insurance for the 5.0.

So I'm in luck and haven't had any more issues since Friday, car drives great just doesn't have that reduced turbo lag anymore
 
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