Hyundai Repair: P0302 Check Engine Code, spark plug wires, intake manifold gasket

Question
QUESTION: I have a 2002 Hyundai Elantra.  It's getting a P0302 Cylinder 2 misfire.  I've changed the spark plugs & the spark plug wires without any success.  I also had the fuel system cleaned.  The car drives fine, plenty of power.  The only issue seems to be a very rough idle.  I tried switching plug wires but it ran so rough I was afraid to drive it & the code seems to take several drives before it comes back on.  I do have a autoscanner & here are the results from that:
Engine RPM:  883 RPM
Load Value:  38.0%
MAP Sensor:  55 KPA
Short Term Fuel Trim1:  4.6%
Long Term Fuel Trim1:  .7%
Short Term Fuel Trim3:  -100.6%
Long Term Fuel Trim3:  -100.6%
Vehicle Speed:  0 MPH
Fuel System 1:  CLSD
Fuel System 2:  N/A

Any help would be appreciated.


ANSWER: If the vehicle accelerates normally, I'd suspect an intake manifold gasket leak.  To check for this, start the engine and spray around the gasket near cylinder #2 with a combustible aerosol such as carburetor cleaner.  If the engine's idle smooths out or increases speed, the engine is sucking in the cleaner through a vacuum leak, quite possibly at the intake gasket.

I presume the data you're giving me above are the freeze frame data from when the code set.  If so, was there a data point for the coolant temperature?

---------- FOLLOW-UP ----------

QUESTION: Yes, I was using freeze frame data & I gave you all that was provided.  But the temperature doesn't seem to be any higher than normal.  This doesn't sound like a simple repair.  Is there anything I should tell the repair shop?

Answer
I wanted to know about the coolant temperature because problems with partially clogged injectors often happen only during a cold start.  So I was curious to see whether that was the case here.

Just give the shop the facts and allow them to reach their own diagnosis.  So report your symptoms, the fact that you installed a code reader and received P0302 and have already replaced the spark plugs and wires.  Also, if you've turned out the check engine lamp, wait until it comes back on to take the car in.  This will ensure they have the opportunity to see the trouble code and freeze frame data on their own.