hey guys, got a 07 escalade with the 6.2l v8. its got 340,000km on it and has been running great, never had any engine issues other then the piston slap and noisy lifters so i have noticed that over the past 50,000 km the truck has had this problem but back in the day it would only do it if i let the truck idle for 4-5 minutes (which i rarely would ever do) and it just gradully got worse and worse and now it "misfires" at idle within 15 seconds so the thing is whenever i come to a stoplight and stay stopped for like 15-20 seconds, ill get the message that says " stabilitrak off service traction control" and then the tone of the engine will change and i guess it will sound rougher with a shake, but right when i start driving agian it goes back to normal and then message clears. if i go on the highway, it drives perfect, smooth, good power good revs and never triggers a messsage or anything, but when i come a stop light or any stop, if i wait long enough it will do its thing again.. rough idle, stabilitrak message, and also if i wait like a minute or 2, then the check engine light starts flashing as well, i believe this is because the truck thinks its misfiring or is misfiring and thats why the check engine light flashes. I have also noticed it started doing it earlier lately, like within 5-10 seconds of being stopped anywhere whether its thru the drive thru or at a stop light etc or a long stop sign, it will come up and say "stabilitrak off service traction control"" and the tone of the engine changes like it sounds different then if i wait a little longer, the check engine will begin to flash. however right when i resume driving and my revs get higher etc then the messages dissapear and the truck drives normal and no check engine flash firstly, the codes i get are p0308 so i know there is a misfire P0036 HEATER CONTROL CIRCUIT BANK 1 SENSOR 2 P0056 HEATER CONTROL CIRCUIT BANK 2 SENSOR 2 P0449 EVAP EMISSION SYSTEM VENT VALVE/SOLENOID CIRCUIT P0452 EVAP PRESSURE SENSOR/SWITCH LOW P0308 ENGINE MISFIRE CYLINDER 8 i also do have some evap codes but have had those forever so im not a mechanic on my own but i swapped coils and tried to see if the misfire stops and it doesnt. i also swapped the plugs and wires around and still has the same problem. the plugs and wires are relatively new only 50,000 km on them. i used my code reader and traced it as a p0308 so i swapped a brand new spark plug into that cylinder and still has the same problem. but have showed it to a local indie mechanic and he did a leakdown test got 6% so he said the engine is still strong, he said compression test was above 200+ for all cylinders, lastly i believe he said he changed the intake manifold gasket but it still has the same problem. he also said the wires are good too. i then took it to GM for a diagnosis and they said this "PO300 MISFIRE. MISFIRE IS ON CYLINDER 8. THE IGN. COIL AND WIRE ARE GOOD. COMPRESSION IS OK. HOOKED UP INJECTOR BALANCE TEST FIXTURE. ALL INJECTORS ARE GOOD. SUSPECT CAMSHAFT ISSUES DUE TO NOISE IN RIGHT REAR BANK AT HIGHER RPM. WOULD NEED ENGINE DISASSEMBLY TO FIND " anyone have any luck? i was reading more and someone said when the engines get gunked up and old, the vvt goes wonky and ends up causing this? but not sure if thats the truth so i wanted to ask, any chance this could be an easy/cheap fix? if not, then whats the worst that could happen by me driving this still? like am i doing way more damage by keep driving it? like my reasoning is that if the fix is expensive i am just going to drive it till it dies because the engine already has enough clicks and i would rather spend the money on a different vehicle. but if it is a cheap fix or easy then might as welll get it fixed.