Originally Posted by hotairgypsy
i am troubleshooting right now around the same thing...in my case i did the buzz test and all sounded fine...did the contribution test and in my case #8 P0284 code...my question in my case is if it is a bad injector do you replace the one or all...
Are you sure #8 is bad? It's pretty common for #8 to fail a CCT but be perfectly fine. I believe #3 also occasionally has this issue.
Replacing 1 vs all is kind of a personal opinion. You can do it both ways. Depending on how many miles are on the injectors would make my decision. I would rather replace everything the first time and not have to do it again. But then again, a bad injector could be a great excuse to upgrade.