really talked to my service manager about my car for the past couple years. last summer i had a misfire problem that i just couldn't figure out. this fall i had come to the assumption it was the injectors. i asked him about the sib with replacing them. november he said bring it in and well read them and if they are bad we'll replace them. my warranty was up last june. i asked him if i should take the JB4 out or if it really mattered. he said to take it out. they dont like to see that when we make the claim. pretty good guy. glad i got to know him through getting my car serviced there alot. ended up me being the smartest person alive and mixing the rear O2 sensors when i installed downpipes last spring.