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Discussion Starter · #1 ·
Throwing P0300/303/304 codes for random misfire and cyl 3/4 misfire and 2 mechanics have already failed to diagnose.

Car runs normal after clearing the codes and resetting ECU on cold start but codes will come back at warm start or warm idle. Warm start/idle is also very rough, guaranteed misfire, and almost stalls out of not given gas.

What's been done so far: Spark plugs replaced, coil connectors replaced, coil pack for cyl 3/4 replaced, voltage check on wires was good, MAF cleaned, TB cleaned, air filter vacuumed

Any ideas on where to look next? I'm unsure if it's an injector problem as the car can run smoothly on cold start.

Any input is appreciated. Thanks!
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