Hello everyone I hope the very knowledgeable people here can help me out. I have a rough idle problem that has been driving me crazy for some time now. I have a 99 firebird trans am m6 with 69k miles. It has a K&N cold air intake and a borla cat back (those are the only mods to that i know of). In trying to fix this issue i have replaced the spark plugs twice (right now ngk tr55 ix's are in there) i have MSD wires, which i bought new. I have replaced the fuel filter, both front 02 sensors, pcv valve and the IAC. I have cleaned the MAF multiple times and cleaned the throttle body to the best of my ability twice. I have also disconnected the Maf and let it run and it may have small difference but if it did it was almost not noticeable. I have also cleaned the IAT sensor as well and checked the coolant temp sensor, (wires looked fine, didnt see any cracks in the connector). I have also checked for vacuum leaks multiple times and found none so far. I also had the drivers side cylinder head replaced (intake manifold bolt snapped off into the head)

I have hooked up my scanner multiple times (bluetooth obd2 and the torque app)
Im not throwing any codes but i will let you know what i have noticed.
When the MAF was disconnected i threw a code but my dash never lit up (i know the light works because i had to replace the led for it and i see it light up when the car starts.)
During some live data monitoring i have noticed cylinder 6 and 8 have 2 misfires each incredibly briefly and then none for a extended period of time. (iv only seen this once) After running some data logs i have also noticed misfires in cylinders 2 and 5 again a count of only 2.
I have also noticed some failures in the mode 6 data however it being mode 6 data its accuracy is questionable. (TID: $0c CID:$20 misfire counts for last/current driving cycles(calculated) max:278, current: 53000 TID: $0c CID:$30 misfire counts for last/current driving cycles(calculated) max:153 current:63000)
I have also started noticing a fuel smell, which is new, its normally only at startup and i smell it occasionally going down the road (i dont see any leaking fuel around the injectors and the ohms reading was accurate)
i am at about 21hg vacuum i believe (which from the research i have done, that is about right)
The idle is not steady, it floats up and down from about 790 to around 805

I appreciate any help that is provided, i also apologize in advance if this is in the wrong place.
Logs are also attached for those who wish to view them, if they can be useful.

Mike

 

Update:. I ran a second pass of logs and I saw more misfires. I'm now showing misfires in every cylinder but cylinder 4.
I decided to unplug the maf and run the same route and data log as well. No misfires and the idle was definitely better. I know that just because it ran better with the maf disconnected doesn't mean I have a bad maf. I am open to suggestions.

Anyone?