PST is -8, PDST is -7 relative to UTC but that is probably not the major problem though it could be slowing things down quite a bit. It is analogous to moving your presumed position about 800 miles at your latitude. Time is used along with the almanac and your presumed position to estimate the doppler shift of the carrier and hence target the search. I don't know about the patch but a sign error (UTC +7 instead of UTC -7) would probably slow the aquisition down to several tens of minutes at least. Trying different timezone offsets could be revealing.

Fast moving cars are really slow compared to moving satellites so the caution you quote relates to obstructions that interrupt data collection not the above mentioned doppler estimate.

The spec I found stated 125 ma at 5 volts for the Rockwell version of the receiver.

At some point you may want to consider writing off your $9.50 (plus tax) and invest in a less compromised receiver

Lynn