Chevrolet Repair: 87 s10 blazer stumbling at cruising, s10 blazer, chevy blazer

Question
Hi,
I have a 1987 Chevy blazer 4x4 with the 2.8L What she is doing is on a steady cruise she stumbles & from a standing start she hesitates. When I first start shes fine but as soon as the temp gauge reads 210 which only takes 10 min. of driving these problems occur. I have replaced the coolant sensor radiator thermostat 185deg. radiator cap & have felt for a surge in the upper hose. I have also changed the o2 sensor as this is the only fault my check engine light gave me. I just have never had a vehicle hit 210 deg. in 10 min. I have also changed the temp sending unit. These problems only ocur at that temp any information you can give me would be great!. Thank you for your time.

Answer
First things first it sounds like you have low fuel pressure.  You shouold have it checked that will cause the drivability problems.  As far as the tem gauge it coud be that your dash unit is of a little bit.  If it is not overheating I would not worry about it 210 is normal operating temp