Bosch dishwasher SHX46A -cycle runs too long (4 hours)- items still wet. The economy cycle also runs too long - should be about 80 minutes and it ran for 200 minutes.

It sounds like there's a problem with the dishwasher's heating element. The dishwasher uses the heating element to heat the water to certain temperatures, and it will wait (run for extra time) for the water to reach this temperature, and may eventually give up. When it's time to dry, the dishwasher uses the heating element to steam dry the dishes. If you're not technically savvy, you will probably need to have a pro work on the machine, but first check to make sure there's not hard water scale buildup on the heating element. If you're brave enough to work on the machine, you should check to see if the element's plugged in, check its resistance to make sure it conducts electricity, check the element's switching components, and finally the dw's computer board. There's a chance that the machine is just stuck in a loop or something. You should try turning off the circuit for a few minutes. There's a chance it may reset and start working.

These dishwashers often had trouble with the relay controlling the heater element, and the problem was with the relay and NOT the element, so replacing the element won't help. Look for a burnt-looking pin on the bottom of the control board inside; the solder has generally melted off. Ideally, replace the relay, but resoldering and/or strengthening connections with soldered-on wire can get it working again. Search for "Bosch relay repair" for more info.