I lost my oil cap for a 5.7 gsi engine. I ordered a replacement on line but I am out of service for a week. I was told by the marina that I could use a a gm oil cap till it comes in. When I went to the auto parts store I found that there are about 20 different caps! Does anyone know what cap to get? It is a 5.7 GSI PEFS 4012032575