Review on ACDelco D521C Ignition System: Original Equipment for Optimal Performance by Dave Russell

I had an engine problem for a while but I just couldn't figure out what the problem was. In the end they told me that the ignition coil was defective. After purchasing this product and having it delivered to your home. He went to the car, took off the old one and put on the new one. Before installing the new one, I compared it with the old one. All boots were found to have cracks and the inside of the boots where they connect to the spark plug looked poor. After installing the new one, I had to wait a few days for the engine to start, but it never did. Now the engine runs very quietly. Above all, the mileage has also increased. It took a long time to replace this folio.