Q: Broken tension adjuster on serpentine belt. How much, and how long should it take to fix?
A: Actually common on these...... takes about an hour of being angry and getting scraped-up hands, depending on tools and ability..... costs vary as to location.... Ed
Q: Smokes at idle only burns a quart of oil on a 2300 mile trip burns more when ever it idles for over a minute when outside temp is cool does very little smoking.
A: If you have a V6 engine you probably need valve guides.
Q: Did a check on a snap on computer. It came back with #3,5 injector not working properly. Cleaned contacts to injector and checked main connector to fuel injector harness its fine. Its still chugs and shakes. Checked wires and plugs and changed them too. The probelm is still there. From start to about 100 km it breaks down alot. From 110 to 120 steady its not bad. But when its starts to chug shake and vibrate its hard to get out of it.
A: Sounds a lot to me like you need to replace the injectors indicated (this, based on the information you supplied). Ed