Is my HC-SR04 faulty?

I got a sonic range sensor with my starter kit, been testing pieces all day, but when i got to this one i ran into a problem.

Running a tutorial code (actually tried 5 different once) i always get the same result.
The range is always between 3200-3300 no matter what.

last code i tried was:

(cant show wiring, but im very sure its as it should be. trig to 12, echo to 13.
ground and 5 v. following the labels on the sensor.

any ideas?

If you cover the receiver or the transmitter with a thumb, you shoud get a reading of 0 (and a delay of up to a second, depending on the library/code).

Nope, nothing changes, keeps the range around 3200