Troubleshooting Misfire

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switch

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Yesterday I went WOT and shortly thereafter got a misfire. I was able to get it home, as I was thankully only .5 mile away from my house.

Body is a 2010 SHO
Motor is a 2013 SHO PP

The codes were:
P0303
P2196
P2198

I changed all the plugs today with Motorcraft SP-534 plugs and checked that every coilpack was getting spark (they were).

Still, misfiring, running rich, smells unburnt fuel.

Any suggestions or help would be appreciated.
 

6500rpm

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No related TSB's. Was sparkplug #3 fuel soaked? You probably already know this, but P0303 is cyl 3 misfire and the P2196/2198 are just O2 sensor stuck rich codes. If you put a spark tester on #3 coil pack and it fired, it almost certainly has to be an injector stuck open on cylinder #3 and the plug would have been fuel fouled and the check engine light was probably flashing. If you can get a noid light plugged into the #3 injector connector and it flashes it would rule out any electrical input issues. The fact that it happened when you went WOT tends to make me think mechanical injector problem.

Is it tuned? It did have this SSM on the Ford site. I'm thinking someone else posted a "like" issue recently involving a injector stuck open.

SSM 45788 - Some Vehicles Could Exhibit Misfire Codes After Certain Repairs - Multiple Vehicle Lines
Some vehicles equipped with On Board Diagnostics (OBD) misfire monitor neutral profile learning capabilities may experience the MIL illuminating or flashing, accompanied by one or more engine misfire related codes(P030X). These faults can be a result of the crankshaft position sensor profile (MP_LRN) not being relearned after engine and transmission repairs. The MP_LRN data is no longer cleared with a battery disconnect. In order to properly reset the Misfire Profile, a KAM clear must be performed. Repairs that can require relearning of the MP_LRN data with IDS include: crank sensor, trigger wheel, engine timing, and any time the engine or transmission (including DPS6) is removed. From the IDS toolbox select "Powertrain", "Service Functions", then "Misfire Monitor Neutral Profile Correction" and follow the on screen prompts.
 
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switch

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Yep, the plug was a little wet and it was the only one that smelled like gas.

No tune on it or anything like that. Thanks for the additional info, I'll have my techs check it out.
 

SHOdded

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Very possibly injector and/or valve cover leak. Very common for the leak in that location.
 

JimC

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My guess is the crank relearn process wasn't done. You obviously replaced the engine from your description.

I had the same thing on my 2013 Mustang after an engine swap. If you have an SCT X4 you can do the relearn yourself. If not, then a quick trip to the dealership will take care of it.

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switch

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Yeah, I don't think the crank re-learn process was done.

SHOdded, you mentioned this is a common problem there. Do you have links to other threads on that issue?

Thanks!
 

SHOdded

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Don't know if there are threads on this forum, but you can find some over at ecoboostperformanceforum.com. The leak usually afflicts 2013+ engines, but there is at least 1 instance of a 2010-12 engine, and strangely enough on Bank 2, not Bank 1 IIRC. Since it is a valve cover gasket leak, it's pretty easy to spot if you see oil in the plugwell when you pull the COP.
 

switch

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No oil in the plugwell. Hoping for a stuck injector...
 

JimC

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No oil in the plugwell. Hoping for a stuck injector...
If the crank relearn process wasn't done then it isn't an injector issue. You get the same symptoms that you described from the lack of crank relearn.

The timing is off if the relearn process isn't done. That of course can cause more problems. Since the ECU doesn't know where the crank really is, and the tune may be calling for 15 degrees of timing, you could be throwing 30 degrees at it.

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switch

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The crank relearn process was done. The motor ran fine for about 12,000 miles after the swap.
 

JimC

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The crank relearn process was done. The motor ran fine for about 12,000 miles after the swap.
So did my Mustang, then I kept getting a random mis-fire.

Double check the status of the relearn, and make sure that it isn't the issue.

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switch

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Heard back today, turns out it's a stuck injector. I think after I get this fixed, I'm just gonna sell the thing...
 

switch

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Yeah, I'm gonna replace all six. I got a warranty with the new motor, so hopefully they will cover all 6.

I've already got about $3800 in it, additional to what I paid for it, due to the first motor blowing. I suppose the positive is that now it has a 2013 PP motor (and soon, 6 new injectors).

I don't know if I could get out of it what I have in it at this point. While the 2013 PP motor is a good selling point, at the end of the day, it's still a 2010 SHO with 110k miles on the body, and 40k on the motor.
 

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