TrackTech Fuel injector seals are usually made of polyurethane or nitrile rubber due to their fuel resistant properties. While the o rings are made to be heavy-duty because using them for a longer period can eventually make it wear out and cause issues with the vehicle. On a general note, the bad or failing o rings will produce some symptoms that can alert the vehicle of a potential issue. So, we have mentioned a few of the symptoms of bad Fuel injector o rings as below:
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