Ecoboost Performance Forum

Ecoboost Performance => Troubleshooting, Maintenance, TSB Articles => Troubleshooting => Topic started by: Matt on September 26, 2015, 01:58:06 PM

Title: P0304 code
Post by: Matt on September 26, 2015, 01:58:06 PM
Hey all,
New to the forum with an issue. 2010 flex awd eco boost with an error code p0304. Turned on when passing and was flashing on the initial pass then went solid. If I get on it, the light will flash again then go back to solid. I'm not feeling the "miss" or seeing any other affects other than the mental anguish. It has 29k and have only had it for 2k. Thanks in advance and look forward to chatting.
Title: P0304 code
Post by: slurppie on September 26, 2015, 02:16:30 PM
Do a search for that code as there is a thread that speaks to it. It was a bad plug causing a misfire. I would link to it if I knew how (Tapatalk).
Title: Re: P0304 code
Post by: glock-coma on September 26, 2015, 02:19:13 PM
Flashing light is no Bueno.
The ecu is cutting power to prevent damage to engine.
Being a 2010 could be o2 sensor related or fuel injector related. What exactly is code p0304?
Title: Re: P0304 code
Post by: glock-coma on September 26, 2015, 02:19:42 PM
Also welcome to the forum
Title: Re: P0304 code
Post by: ZSHO on September 26, 2015, 02:37:15 PM
I wouldnt drive the car at the moment,sounds like an issue on Bank 2,the front side of the engine on the passenger side is #4 injector,which could be a misfire or a leaking injector,any smell of gas or smoke?  Z
Title: Re: P0304 code
Post by: SHOdded on September 26, 2015, 03:00:47 PM
http://www.obd-codes.com/p0304 (http://www.obd-codes.com/p0304)

Luckily, this cylinder is easily accessible.  Radiatorside, leftmost cylinder.  Hopefully its just a plug or coil.  Fuel or oil soak on plug or coil would be more work to resolve.

And welcome!
Title: Re: P0304 code
Post by: pmezo33 on September 26, 2015, 03:19:22 PM
Replace the plug and switch the coils with another cylinder.  See if the misfire code follows where you moved the coil.  Hopefully a new plug does it if you don't get the code again.
Title: Re: P0304 code
Post by: BiGMaC on September 26, 2015, 07:14:54 PM
Quote from: glock-coma on September 26, 2015, 02:19:13 PM
Flashing light is no Bueno.
The ecu is cutting power to prevent damage to engine.
Being a 2010 could be o2 sensor related or fuel injector related. What exactly is code p0304?
glock-oma is right! Your manual will tell you that when the CEL is flashing you have exceeded the ECU's ability to adjust enough to be a safe level of engine protection and the manual will tell you not to drive it.
Title: Re: P0304 code
Post by: SammyB on October 22, 2015, 09:09:10 PM
The main reason it is flashing is to prevent you from a catalytic converter meltdown. It detects a cylinder misfire on cylinder #4. The reason it is flashing when you passed a car is because of the extra load you are placing on the engine. If it is spark related, then that cylinder is still getting fuel most likely but it is not getting burned. Therefore you are dumping raw fuel into a cat that's well above 1000 degrees F. I can't tell you how many cats I have seen at my shop that have actually melted through and liquefied the metal case! I realize this thread is almost a month old but did you resolve the problem? The other poster who recommended swapping coils is right although I wouldn't do several fixes at the same time. The plug is most likely the culprit but swapping the coils is sage advice.
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