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S550 GT350 issues - wrench warning light

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Hello! I recently purchased a 2018 GT350 with 17k miles. The car has been an absolute blast but I recently experienced a weird issue where the wrench warning light came on, followed by a hill assist unavailable message. This happened at highway speeds after roughly 35 mins of driving.

The dealership is telling me the previous owner already had a TSB addressed for a similar issue at 12k miles, before I purchased the car. But I saw it again at 17k miles, so it clearly wasn’t fixed properly. Does anyone have any ideas as to what this could be?
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,420
8,346
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
A past customer of mine had a problem with this and the Ford Tech at Woodhouse Ford ( where I used to work ) told me it was an issue with the throttle body. I am not positive as this was back in 2017, but I think it was a problem with a sensor.
 
A past customer of mine had a problem with this and the Ford Tech at Woodhouse Ford ( where I used to work ) told me it was an issue with the throttle body. I am not positive as this was back in 2017, but I think it was a problem with a sensor.
Appreciate the reply! Dealership near me locally did nothing to resolve the issue and sent me home. I’m looking for someone I can trust to take a look at the car, will forward this info on to them.
 
UPDATE: Drove the car home today and on my way back the wrench light popped up again followed by the "hill start not available message".. Car felt okay to drive for the most part. I did feel some weird behavior with 3rd gear where it almost felt like the car was trying to auto rev match my shift? This only happened 2 or 3 times on my drive home which was roughly 25 miles.
 
Forgot to mention one thing. Once I got the car back into my garage, I tried restarting it to see if the wrench light went away. Unfortunately, it stays on even when the car restarts now and I had to hold down the start button longer than usual, or it wasn't firing up.
 
Hello! I recently purchased a 2018 GT350 with 17k miles. The car has been an absolute blast but I recently experienced a weird issue where the wrench warning light came on, followed by a hill assist unavailable message. This happened at highway speeds after roughly 35 mins of driving.

The dealership is telling me the previous owner already had a TSB addressed for a similar issue at 12k miles, before I purchased the car. But I saw it again at 17k miles, so it clearly wasn’t fixed properly. Does anyone have any ideas as to what this could be?
A5D02CF2-A255-4740-86B0-6CE8C527C9F8.jpeg
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,420
8,346
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
BS-1 might be able to recommend a solid Dealership fairly close to you since he is near the Tampa Metro area.
Good luck , but I am sure there is a Dealer near you that can help you with your issue.
 
BS-1 might be able to recommend a solid Dealership fairly close to you since he is near the Tampa Metro area.
Good luck , but I am sure there is a Dealer near you that can help you with your issue.

Thank you! I love this car and waited a long time to pull the trigger on buying one. Really want to get out there and enjoy it, hoping I can get this issue resolved.
 
7
9
Exp. Type
HPDE
Exp. Level
5-10 Years
Phoenix, AZ
My 2016 GT350 is doing the same thing. I found TSB 19-2135 regarding a transmission output shaft flange nut coming loose. I have an appointment later this week at my dealer to address - hopefully it’s an easy fix. My wrench light comes on and goes off, the hill start message appears, cruise control doesn’t work, and there is major surging at low RPMs!
 
My 2016 GT350 is doing the same thing. I found TSB 19-2135 regarding a transmission output shaft flange nut coming loose. I have an appointment later this week at my dealer to address - hopefully it’s an easy fix. My wrench light comes on and goes off, the hill start message appears, cruise control doesn’t work, and there is major surging at low RPMs!

Ah man, sorry to hear you’re having issues as well! I dropped my car at the dealership today, praying it’s a simple fix. It seems like the previous owner might’ve actually already had that TSB addressed several thousand miles ago and it came back, but waiting on dealership to confirm that for me. This dealership experience has been awful, hopefully your experience is much better. Best of luck and keep me posted. I will provide updates here once I hear back.
 
UPDATE: They finally took a look at my car. Took them forever it’s been brutal with this dealership but they said they are going to address the TSB, replace the A/C compressor, and replace the clutch pedal assembly I believe. No parts until Monday so might not have the car back until Christmas or later. Lets hope these things resolve my issue!
 
Update: Just got car. TSB did not seem to fix the issue. It’s a little better maybe but still occurs. They replaced the clutch pedal assembly as well. In their notes it says they confirmed the issue is fixed but it’s definitely not. Also, they broke my turn signal it seems. My turn signal blinks really fast now inside the car, front left turn signal light is out. Didn’t drop car off like that.

595B4D08-1D39-4178-9093-54E28EF1FA75.jpeg
 
6,360
8,180
I see "removed front bumper" looks a lot like, " I hosed up a turn signal" when I replaced it.

Why would you replace the clutch pedal? that's a pretty stout, non problem thing with these cars
 
I see "removed front bumper" looks a lot like, " I hosed up a turn signal" when I replaced it.

Why would you replace the clutch pedal? that's a pretty stout, non problem thing with these cars

Exactly my thoughts, I certainly didn’t do it haha. Called dealership and no one has responded yet but I’ll have them take care of it.

Looks like they replaced the clutch pedal position sensor. I’m not 100% sure why but that’s what Ford suggested when they called the hotline it seems. Hoping to get to the bottom of the hesitation issue eventually, wont give up on it. Will try again after the holidays
 
Blinker issue turned out to be simple. I took the tabs off under the wheel well and peeled it back a bit. I could instantly see the issue, they forgot to plug the lights back in after pulling the front bumper off during service 🙄. I stuck my hand in there and reconnected the plug.
 

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