If a coil seems to be misfiring or not firing at all, or is causing the Powertrain Control Module(PCM) to set a Diagnostic Trouble Code (OTC) that indicates a misfire, try swapping it with an adjacent coil. If the suspect coil was causing a OTC for one cylinder, it will likely set another OTC when it's installed above another cylinder. If this is the case, the coil is probably defective because it's unlikely that the harnesses for two adjacent ignition coils would both be defective. At any rate, no further testing is possible at home. If you're not sure whether you should replace the coil at this point, consult a dealer service department or other qualified repair shop. To replace, disconnect the cable from the negative battery terminal. Remove the engine cover. If you're removing an ignition coil from the left cylinder bank, remove the air filter housing and the air intake duct, then detach the engine harness and push the harness aside as necessary. Also move aside any hoses routed over the ignition coil. If you're removing an ignition coil from the right cylinder bank, detach the engine harness and push the harness aside as necessary. Also move aside any hoses routed over the ignition coil. Disconnect the electrical connector from the coil. Remove the ignition coil mounting bolt and remove the coil. Installation is the reverse of removal.