In the code that LinkMTech provided there should be no issue with the PAUSEUS or PAUSE commands.
distance:
PULSOUT trig,1 ' each count = 10us
PAUSEUS 120 ' Wait for transmit pulse to complete
PULSIN sens,1,dist ' will time out in 655ms if nothing received
dist= dist/15 'convert to inches
PAUSE 100
RETURN

END
There is a minimum delay between the time the device reacts to the input (PULSOUT) and the time it provides an output (to be read by PULSIN). This time is defined by the 8 40kHz bursts it sends. The device does not raise its output high before the burst is sent (that is in the datasheet), so that means that you could use an approximate delay no longer than 200us between PULSOUT and PULSIN commands and still be ok. LinkMTech suggested 120us to allow for margin; that should be no problem. The other delay, the one which occurs after the PULSIN, represents how much to delay before the next time it tries the measurement again. This again should not be an issue.

You certainly need a scope, but not to test your code (since your code looks fine, and it matches BASIC STAMP code and many others which work with modules like the PING, and Devantech's SRF04 modules. You need the scope to see if the module you have is doing what its datasheet claims it does. Also. maybe a pulldown (say 10-20k on the GPIO4 may help - perhaps the SR module does not pull to ground too well).