Chevrolet Repair: 4.3 vin W tps, throttle position sensor, resistance measurement

Question
I have a 95 blazer, 4.3, auto, 4wd.  runs fine up to half throttle, then hesitates and bogs down.  I replaced to throttle position sensor and noticed something stange--when I measure the resistance directly at the sensor, it ranges from 1.8 at idle up 6.8 at wot, I believe that is an acceptable range.  However, when measured through the pigtail, idle is roughly the same, but it tops out around 2.5 (coincidentally at about half throttle).  Is this right?, if not how do I go about fixing this problem?
Thanks-- Nick
F.Y.I.-Nearly all ignition components are new as well as the fuel pump and filter.

Answer
Hi Nick,
That doesn't sound correct to me. But I am curious how you are measuring the resistance and getting 1.8 to 6.8.
I would expect the resistance measurement to be in ohms,
unless you are using jumpers.
I would want it to max out pretty close to the refference voltage. Have you checked both TPS's, and get about the same?
Any green in the connector cavities?
A scan tool connected and turned to read sensor outputs would sure help.

Van