Hi everyone I have a 2006 2.4 in a s40 and I just finished installing a new motor but the timing belt wants to work its way out and off the gears could this be a tensioner issue I've tried a new water pump new exhaust cam gear and 3 different tensioners and 2 new tensioner bolts and 2 new belts scared to start it would be fatal if it came off any suggestions would be so helpful thanks

 

The only thing that's going to cause that is if one of the pulleys isn't square with all the others. Double-triple-check your work. Did you use the cam position lock to install the belt?

And yes, starting it and losing the timing belt is game over for the engine, so get it sorted before trying to start it.