Check engine light unexpectedly on!!

[loucas-2021]

Would like some advice on what it might be and what to expect from dealership.

My car is a 2020 Mustang GT with around 18500 miles....never tracked or raced, naturally some spirited driving. And a dealer installed FP performance pack (cold air, tune and throttle body).

So I left gas station quickly and thought I detected a misfire but was at work so parked car for the day. Later on on, leaving I started car and noticed check engine light was on but car seemed fine so drove home like 18 miles. Next morning light still on so I call dealership. They logged on to Fords service and do detect a misfire and suggest I bring car in for service. So called Ford roadside to come flatbed car to dealership.

About 1 month ago I did an oil change, air filter (FP cold air) tire rotation etc. All good...

My new car warranty is up 12/29/23 and did have a "wrench light" on for a minute this past summer. Stalled car in driveway but next startup "wrench" light was off...

So what could this misfire be and what should I make sure Ford repairs now while still under warranty???

Did you install the GT calibration kit with Cold Air Intake and throttle body from FP? I have the same thing installed. I hope your issue is not related to the kit. I installed mine at 5k miles. I'm at 24K now. So far no issues. BTW I think you can use the calibration tool to read codes if I'm not mistaken.

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[Pilafiction]

Without knowing exactly what misfire code it has helping is almost impossible. Even knowing the specific code is not easy because it can be so many things.
Random or multiple misfires, I'd be thinking vacuum leak or maybe the cam adjustors. Individual cylinder misfires could be as simple as a bad plug or coil or as drastic as a leaking head gasket, along with vacuum leaks, cam adjustors, etc.
So you can see why it's difficult to point to any one thing over the internet.

Did you install the GT calibration kit with Cold Air Intake and throttle body from FP? I have the same thing installed. I hope your issue is not related to the kit. I installed mine at 5k miles. I'm at 24K now. So far no issues. BTW I think you can use the calibration tool to read codes if I'm not mistaken.

yup, same package from FP. In fact this dealership where car is now, just replaced the cold air filter(blue one) last month. I doubt that package had anything to do with this . The dealership reopens today so should have more information very soon.

 

[Keeffa]

Would like some advice on what it might be and what to expect from dealership.

My car is a 2020 Mustang GT with around 18500 miles....never tracked or raced, naturally some spirited driving. And a dealer installed FP performance pack (cold air, tune and throttle body).

So I left gas station quickly and thought I detected a misfire but was at work so parked car for the day. Later on on, leaving I started car and noticed check engine light was on but car seemed fine so drove home like 18 miles. Next morning light still on so I call dealership. They logged on to Fords service and do detect a misfire and suggest I bring car in for service. So called Ford roadside to come flatbed car to dealership.

About 1 month ago I did an oil change, air filter (FP cold air) tire rotation etc. All good...

My new car warranty is up 12/29/23 and did have a "wrench light" on for a minute this past summer. Stalled car in driveway but next startup "wrench" light was off...

So what could this misfire be and what should I make sure Ford repairs now while still under warranty???

Sounds like you may have got bad fuel.

 

[young at heart]

And I used to set my points with a match book cover and timing by ear.
(Edit)- Lol. FCOL, It’s a very special moment when you realize you sound like your dad.

I remember being a broke teenager having to decide between a new set of points or a cold sixer of brew. Problem temporarily solved with a business card soaked with a little lighter fluid, both borrowed from the old man. You did what you had to do!

I had a friend who could synchronize the carbs on our Triumph Bonnies and Nortons by ear. I alway admired that.

 

[Pilafiction]

Sounds like you may have got bad fuel.

Could be although I've been using Gulf premium, 93 most of the time...

 

[IPOGT]

Could be although I've been using Gulf premium, 93 most of the time...

NO NOX.

 

[Deleted member 69311]

Buy some isoheet and pour it in the gas tank after refueling. Probably some water in your injectors so it’ll clean it out. Don’t gas up at cheap places. A lot of gas stations use the same vendors. Stick with shell and chevron for quality gas.

Towing your car to the dealer because of a check engine light is wild to me!

 

[Pilafiction]

Buy some isoheet and pour it in the gas tank after refueling. Probably some water in your injectors so it’ll clean it out. Don’t gas up at cheap places. A lot of gas stations use the same vendors. Stick with shell and chevron for quality gas.

Towing your car to the dealer because of a check engine light is wild to me!

 

[Pilafiction]

Dealer suggested the service after diagnosis over phone, car under new warranty and coyote gen 3 engines are expensive. Straight forward nothing wild about it.

 

[Deleted member 69311]

Dealer suggested the service after diagnosis over phone, car under new warranty and coyote gen 3 engines are expensive. Straight forward nothing wild about it.

Just a suggestion. Buy an ODB II scanner. It’ll save you time so you don’t have to wait for the dealer to tell you what’s wrong.
Misfires would be a blinking check engine light.
Most of the time it fixes itself.

 

[ORRadtech]

Just a suggestion. Buy an ODB II scanner. It’ll save you time so you don’t have to wait for the dealer to tell you what’s wrong.
Misfires would be a blinking check engine light.
Most of the time it fixes itself.

Basic OBD readers are dirt cheap as long as you don't mind using your phone to link to it. Even stand alone ones are pretty darn cheap. I agree that owning one can provide a lot of information pretty much immediately without having to rely on anyone else.

Misfires only trip a blinking CE light if they're active. A solid CE can indicate a random, multiple or specific stored misfire.

Misfires don't really fix themselves with the possible exception of getting a bad tank of fuel.

 

[Garfy]

Basic OBD readers are dirt cheap as long as you don't mind using your phone to link to it. Even stand alone ones are pretty darn cheap. I agree that owning one can provide a lot of information pretty much immediately without having to rely on anyone else.

Misfires only trip a blinking CE light if they're active. A solid CE can indicate a random, multiple or specific stored misfire.

Misfires don't really fix themselves with the possible exception of getting a bad tank of fuel.

The good part about a code reader is that you'll get some idea on what system is at fault, so if the shop gives you some guff about something totally unrelated, well at least you have some ammo. The DTC you get doesn't necessarily mean that component is faulty; it just tells you that the PCM saw something on that circuit that it didn't like and set the code for it. Many DTCs can be caused by a number of different things so they shouldn't throw parts at it like so many used to do in the earlier days of OBD systems... especially since today's stuff is so much more expensive.

 

[Dave2013M3]

To the OP, any news on what it was?

 

[Pilafiction]

Just a suggestion. Buy an ODB II scanner. It’ll save you time so you don’t have to wait for the dealer to tell you what’s wrong.
Misfires would be a blinking check engine light.
Most of the time it fixes itself.

It wasn't blinking and when still on next morning...dealer looked at it today so should have some news next week. Appreciate the input.

 

[Dave2013M3]

It wasn't blinking and when still on next morning...dealer looked at it today so should have some news next week. Appreciate the input.

Any updates?

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