Aloha Folks, new here and thankful for this site. I have a 2007 Sport Trac, V6. Did a bunch of items the other day including installing one of Zabteck's metal thermostat housings which are great! We also did the valve cover gaskets and lower manifold gaskets/rings. After it was all put back and started up, the truck ran rough, was smoking. My mechanic shut things down, started to do tests. He found that one injector was not closing, staying open and fuel was just pouring into the chamber. He took off the electrical connection, turned on the ignition and it was still happening so we knew it was a mechanical issue with the one injector. Luckily I was able to find 1 brand new injector at an Autozone, installed it and put everything back together. Vehicle runs great. Question: My Trac has about 145K on it. When if any should we change out the fuel injectors? If so, would you recommend the rebuilt/refurbished Bosch ones I see a lot on ebay or is it better to buy new Ford Motocraft ones? I just don't want this to happen again for a while but also don't want to do something if it is not needed. Look forward to your suggestions, advice. Thanks, Mahalo!