OBD-II code · Fuel & Ignition
One specific cylinder is misfiring. The short list: coil, plug, injector, compression, or wiring to one of those. Most are cheap; compression problems are not.
Swap the coil without checking anything else. Coils are the most common cause — but not the only one, and repeat visits are guaranteed when it is not.
Typical guess-and-swap cost: $150–$300 (coil swap) when the real issue is head work — or vice versa
Swap the coil with another cylinder and see if the misfire follows it. If it stays on #1: plug, then injector balance, then compression. Ten minutes of logic instead of a parts lottery.
Mobile service in Canyon Lake, San Antonio & Austin. Written report with root cause — see a sample.