Hello Everyone

I'm brand new to the forum, and begging for help! I've looked around at other threads on rough idle issues, and just cant seem to get to the bottom of mine. I'm providing all the info that I can, in hopes that you all can provide me where to go next!

I have a F-150 5.4L Lariat Supercrew- I purchased it only a month ago with 152,550 on it. I drove it over 300 miles home, and it sit for a day. Next time I got into it, drove it about 40 miles and at a stop light, it started to rough idle. It idles extremely rough to the point where it has stalled 3 or 4 times. Generally it continues to run, but I can smell it exhaust smell inside the truck. I had a smoke test performed, and was told there were no vaccum leaks.

Here's what has happened since then:

I took it to a Ford dealer in my area and they told me that the only code was P0304 and P0198. They stated that I needed to replace Coil #4 and that there was in oil code but to check it out again after we fixed the coil mis-fire.

I had ALL 8 plugs changed out with Motor Craft plugs
Changed oil and filter
Replaced Coil #4

This didnt fix issue. I took back to Ford and they stated that P0198 indicated that I needed to replace the Oil Temp Sensor. They replaced the senor reset the light and now it's back on. Same code P0198. They then stated that common issue with these were trottle body issue causing rough idle.

I had the Throttle body replace and clean the Mass Air Sensor based on reading these forums. Later, I replaced the Fuel Modulator thats under the spare tire because dealer said it was also bad. Ended up also replacing the Fuel rail sensor, because I was told it sometimes casues the rough idle. Through all of this, the only code that remains is P0198.

Recently I purchased a OBD2 reader and wanted to present the live data to see if someone saw anything that might stand out that I should focus in on. I absolutely can't afford another trip to the dealer.

**Disclosure-I'm not anything even close to a mechanic. However I do have a mechanic that I can have perform anything I need to do**

TAKEN WITH ACTRON CP9575 READER ON COLD START

ABSLT TPS 13.7%
Engine Speed 836 RPM
BARO PRS "HG" 27.2
CALC LOAD 27.2%
MAF(LB/M) 1.41
OUT TEMP 25 DEGREES
COOLANT 88 DEGREES
IAT 39 DEGREES
IGN ADV 18.5 DEGREES
ST FTRM1 -9.1%
ST FTRM2 6.3%
LT FTRM1 -3.9%
LT FTRM2 3.0%
VEH SPEED 0
ABS LOAD 22.4%
REL FRP 78.66 PSI
FUEL SYS 1 CLOSED
FUEL SYS 2 N/A
REL TPS 2.4%
THROT CMD 3.5%
ABS TPS B 17.3
ACC POS D 18.0%
ACC POS E 29.4%
ACC POS F 17.6%
CAT TEMP 11 746 DEGREES
CAT TEMP 21 746 DEGREES
EVAP PURGE 57.3%
EVAP VP(H20) -2.517
CMD EQ RAT 0.999
02S11(V) 0.560
ST FTRM11 -10.9%
02S12(V) 0.605
02S21(V) 0.125
ST FTRM21 13.3%
02S22(V) 0.685
FUEL LEVEL 47.8%
VPWR(V) 14.551
ENG RUN (M:S) 3:39
OBD2 STAT CA

I know this is long, but I REALLY appreciate any help that someone can provide. The idle issue is bad enough that I do not drive the truck, and have only had it for a month. I've spent over $1500 trying to figure this out, and just cant afford to keep throwing money against the wall!