My 04 F250 5.4l 2V has had a miss on start up for the first 30 sec. It has code P0304 and P0316. I replaced the #4 coil and all new spark plugs with MOTORCRAFT part. Clear the codes and it came back 3 days later. There was no oil or coolant in the plug holes and all the old plug look the same light tan. Do not know hat to do nest. A local shop said the timing chain might have jumped a tooth but do not trust them as they told me the engine needed to be pulled to do a timing chain job. LOL Thank for any help. Unless someone knows a good shop for 5.4 work on Long Island.

 

Yo.

This seems to be a common issue. Start simple even if it seems redundant.

Compression test on those cylinders.
Check to make sure the boots are seated and not cracked. Did you use grease?
Check the problem coils with a test light or multimeter.
Swap the coil packs with other known good ones and see if the code jumps to that cylinder.
Check to see if the intake gasket is leaking. Spray some ether around those ports while running and listen for rpm increase.
You can even test the injectors or swap them with known good ones from other cylinders.
How long has it been since you've changed the fuel filter?
Remove the plugs and check for good healthy spark.
Check the gapping in the new plugs.

 

If the timing chain jumped a tooth the misfire would be there all the time. I’d start by doing a cranking cadence check on the engine when cold (or just go straight to a compression test).

— Dave

 

Injector? ----

 

I have a new injector I can try, but wouldn't there be a code if it was a problem?

 

Yo

​​​​​​As far as I know the only codes for the injectors are either circuit low or circuit high. Codes P0261-P0283 deal with the injectors. But the computer will only detect issues with the wiring to each injector. So it will know if the voltage is too low or too high, but not if the injector was operating correctly.

Again, I believe this to be true, but I could be wrong and there may be other codes.

 

{ can replace the injector with the new on I have. I also have new O-rings. I am a little hesitant as I have never changed an injector nor even touch a fuel rail. Just to make sure I am correct the #4 cyl is pass side rear correct?

 

Yo.

First step is to have the engine running and then pull the fuse or relay for the fuel pump. It'll starve itself and then die, leaving your fuel rail non pressurized.

On each bank of the engine there will be a chrome fuel line bolted to the intake manifold. I think they're 8mm. Anyway, unplug the wire connectors from each of the injectors and simply pull the fuel rail up and away after removing the bolts.

Cylinder number 4 is the PASSENGER REARMOST CYLINDER.

​​​​Grab the injector and pull straight up and it'll pop free. To install a new injector make sure the o rings are on and fully seated onto the injector. Dip your finger in some clean oil or Vaseline and lightly coat both o rings. Line up the injector and push down firmly but not excessively. Don't twist the injector or spin it back and forth if you can help yourself. You'll likely tear the o ring. Then align the fuel rail with all 4 injectors on that side, pop it down and then tighten the bolts or whatever holds down the rail.

Now hop in the truck and cycle the key a few times after reconnecting the fuel pump fuse or relay. Don't start the truck yet. After 3-5 key cycles get out and check all the injectors and fuel rail on the side you worked on for fuel leaking.

If all is well then hop in and fire up the truck.

 

Thanks Steve for the instructions? I will try this weekend.
Thanks for all the input from all. I will keep you all updated.

 

So codes are back after changing fuel injector on #4. I do not know what to do. I know if I take it to a shop, I hope they know what there are doing. But they are going to want to put another coil, plugs and injector. I already put 2 of each in. Do not know who to trust.

 

Damn that sucks sorry to hear it's still giving you trouble.

​​​​​​Correct me if I'm missing something but so far you have replaced the spark plugs, replaced the coil or multiple coils, replaced the injector and also swapped coils and injectors around.

If that's everything then the only reasonable things to try I can think of would be: checking compression on that cylinder and compare to others, check for intake manifold leaks around #4, or honestly maybe pull the valve cover and just check everything out around #4.

 

It must be a problem with a valve such as a lifter or cam follower, etc.

 

Sounds like you have a blown head gasket or intake gasket, possibly a cracked head. P0316 means misfire on startup. Usually this happens when it's been sitting awhile and coolant has leaked into the cylinder. I would do a pressure test on the coolant when the system is cold, let the pressure sit at 15lbs for about 30 to 45 minutes, then stick a bore scope down the #4 cyl, to see if you have coolant sitting on the piston.
You also said that you swapped the injector and it made no difference. Did you check the wiring harness on that injector to make sure it's actually working?
How many miles on this engine? Maintenance records? Oil changed regular so no crud buildup? Possibly a lifter sticking? Just so many variables for misses.

 

Don't mean to revive a dead thread unnecessarily, but I just wanted to check in and see how everything is going. I'm hopeful you got it all figured out. There was a lot of good advice from others and I wouldn't mind knowing what solved it so I could keep that info in the back of my mind.

Steve

 

I have a 2004 2v that was missing. Changed all the plugs and coils and that solved it. The coils appeared original at 180K miles. The summit racing 2V coils are great quality, and were $180 for all 8. The coils had corrosion in them, be sure to use dielectric grease.

On my 2016 the coils are sparking on the fuel rail. Common issue with 6.2L trucks. Also caused by corrosion and the lack of grease at the factory. There was so much corrosion on top of the spark plug that the spark 'dug' a hole through the side of the coil base. Still ran fine though somehow, no miss. The recommended coil for those was MSD at $500 a set.